diff --git a/.travis.yml b/.travis.yml
index f79cfbb..f2078cb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,18 +1,14 @@
-# system setup
 sudo: required
 dist: trusty
 
-# language setup
 language: node_js
 node_js:
-  - "6"
+  - '10'
 
-# setup yarn
 cache:
-  yarn: true
+  yarn: npm
   directories:
     - node_modules
 
-# command to run tests
 script:
   - npm run test:coverage:report
diff --git a/package-lock.json b/package-lock.json
index 8dc82a2..4c84875 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1646,12 +1646,6 @@
         }
       }
     },
-    "assert-plus": {
-      "version": "0.2.0",
-      "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-0.2.0.tgz",
-      "integrity": "sha1-104bh+ev/A24qttwIfP+SBAasjQ=",
-      "dev": true
-    },
     "assign-symbols": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/assign-symbols/-/assign-symbols-1.0.0.tgz",
@@ -1697,12 +1691,6 @@
       "integrity": "sha512-Wm6ukoaOGJi/73p/cl2GvLjTI5JM1k/O14isD73YML8StrH/7/lRFgmg8nICZgD3bZZvjwCGxtMOD3wWNAu8cg==",
       "dev": true
     },
-    "aws-sign2": {
-      "version": "0.6.0",
-      "resolved": "https://registry.npmjs.org/aws-sign2/-/aws-sign2-0.6.0.tgz",
-      "integrity": "sha1-FDQt0428yU0OW4fXY81jYSwOeU8=",
-      "dev": true
-    },
     "aws4": {
       "version": "1.8.0",
       "resolved": "https://registry.npmjs.org/aws4/-/aws4-1.8.0.tgz",
@@ -1985,15 +1973,6 @@
       "integrity": "sha1-aN/1++YMUes3cl6p4+0xDcwed24=",
       "dev": true
     },
-    "boom": {
-      "version": "2.10.1",
-      "resolved": "https://registry.npmjs.org/boom/-/boom-2.10.1.tgz",
-      "integrity": "sha1-OciRjO/1eZ+D+UkqhI9iWt0Mdm8=",
-      "dev": true,
-      "requires": {
-        "hoek": "2.x.x"
-      }
-    },
     "brace-expansion": {
       "version": "1.1.11",
       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
@@ -2317,12 +2296,6 @@
         "rsvp": "^4.8.4"
       }
     },
-    "caseless": {
-      "version": "0.11.0",
-      "resolved": "https://registry.npmjs.org/caseless/-/caseless-0.11.0.tgz",
-      "integrity": "sha1-cVuW6phBWTzDMGeSP17GDr2k99c=",
-      "dev": true
-    },
     "chalk": {
       "version": "2.4.2",
       "resolved": "https://registry.npmjs.org/chalk/-/chalk-2.4.2.tgz",
@@ -2761,46 +2734,17 @@
       }
     },
     "coveralls": {
-      "version": "2.13.3",
-      "resolved": "https://registry.npmjs.org/coveralls/-/coveralls-2.13.3.tgz",
-      "integrity": "sha512-iiAmn+l1XqRwNLXhW8Rs5qHZRFMYp9ZIPjEOVRpC/c4so6Y/f4/lFi0FfR5B9cCqgyhkJ5cZmbvcVRfP8MHchw==",
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/coveralls/-/coveralls-3.0.3.tgz",
+      "integrity": "sha512-viNfeGlda2zJr8Gj1zqXpDMRjw9uM54p7wzZdvLRyOgnAfCe974Dq4veZkjJdxQXbmdppu6flEajFYseHYaUhg==",
       "dev": true,
       "requires": {
-        "js-yaml": "3.6.1",
-        "lcov-parse": "0.0.10",
-        "log-driver": "1.2.5",
-        "minimist": "1.2.0",
-        "request": "2.79.0"
-      },
-      "dependencies": {
-        "request": {
-          "version": "2.79.0",
-          "resolved": "https://registry.npmjs.org/request/-/request-2.79.0.tgz",
-          "integrity": "sha1-Tf5b9r6LjNw3/Pk+BLZVd3InEN4=",
-          "dev": true,
-          "requires": {
-            "aws-sign2": "~0.6.0",
-            "aws4": "^1.2.1",
-            "caseless": "~0.11.0",
-            "combined-stream": "~1.0.5",
-            "extend": "~3.0.0",
-            "forever-agent": "~0.6.1",
-            "form-data": "~2.1.1",
-            "har-validator": "~2.0.6",
-            "hawk": "~3.1.3",
-            "http-signature": "~1.1.0",
-            "is-typedarray": "~1.0.0",
-            "isstream": "~0.1.2",
-            "json-stringify-safe": "~5.0.1",
-            "mime-types": "~2.1.7",
-            "oauth-sign": "~0.8.1",
-            "qs": "~6.3.0",
-            "stringstream": "~0.0.4",
-            "tough-cookie": "~2.3.0",
-            "tunnel-agent": "~0.4.1",
-            "uuid": "^3.0.0"
-          }
-        }
+        "growl": "~> 1.10.0",
+        "js-yaml": "^3.11.0",
+        "lcov-parse": "^0.0.10",
+        "log-driver": "^1.2.7",
+        "minimist": "^1.2.0",
+        "request": "^2.86.0"
       }
     },
     "create-ecdh": {
@@ -2862,15 +2806,6 @@
         "which": "^1.2.9"
       }
     },
-    "cryptiles": {
-      "version": "2.0.5",
-      "resolved": "https://registry.npmjs.org/cryptiles/-/cryptiles-2.0.5.tgz",
-      "integrity": "sha1-O9/s3GCBR8HGcgL6KR59ylnqo7g=",
-      "dev": true,
-      "requires": {
-        "boom": "2.x.x"
-      }
-    },
     "crypto-browserify": {
       "version": "3.12.0",
       "resolved": "https://registry.npmjs.org/crypto-browserify/-/crypto-browserify-3.12.0.tgz",
@@ -3885,9 +3820,9 @@
       }
     },
     "esprima": {
-      "version": "2.7.3",
-      "resolved": "https://registry.npmjs.org/esprima/-/esprima-2.7.3.tgz",
-      "integrity": "sha1-luO3DVd59q1JzQMmc9HDEnZ7pYE=",
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.1.tgz",
+      "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A==",
       "dev": true
     },
     "esquery": {
@@ -4423,17 +4358,6 @@
       "integrity": "sha1-+8cfDEGt6zf5bFd60e1C2P2sypE=",
       "dev": true
     },
-    "form-data": {
-      "version": "2.1.4",
-      "resolved": "https://registry.npmjs.org/form-data/-/form-data-2.1.4.tgz",
-      "integrity": "sha1-M8GDrPGTJ27KqYFDpp6Uv+4XUNE=",
-      "dev": true,
-      "requires": {
-        "asynckit": "^0.4.0",
-        "combined-stream": "^1.0.5",
-        "mime-types": "^2.1.12"
-      }
-    },
     "fragment-cache": {
       "version": "0.2.1",
       "resolved": "https://registry.npmjs.org/fragment-cache/-/fragment-cache-0.2.1.tgz",
@@ -5147,24 +5071,6 @@
       "integrity": "sha1-GwqzvVU7Kg1jmdKcDj6gslIHgyc=",
       "dev": true
     },
-    "generate-function": {
-      "version": "2.3.1",
-      "resolved": "https://registry.npmjs.org/generate-function/-/generate-function-2.3.1.tgz",
-      "integrity": "sha512-eeB5GfMNeevm/GRYq20ShmsaGcmI81kIX2K9XQx5miC8KdHaC6Jm0qQ8ZNeGOi7wYB8OsdxKs+Y2oVuTFuVwKQ==",
-      "dev": true,
-      "requires": {
-        "is-property": "^1.0.2"
-      }
-    },
-    "generate-object-property": {
-      "version": "1.2.0",
-      "resolved": "https://registry.npmjs.org/generate-object-property/-/generate-object-property-1.2.0.tgz",
-      "integrity": "sha1-nA4cQDCM6AT0eDYYuTf6iPmdUNA=",
-      "dev": true,
-      "requires": {
-        "is-property": "^1.0.0"
-      }
-    },
     "get-caller-file": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/get-caller-file/-/get-caller-file-1.0.3.tgz",
@@ -5296,6 +5202,12 @@
         "unicode-trie": "^0.3.1"
       }
     },
+    "growl": {
+      "version": "1.10.5",
+      "resolved": "https://registry.npmjs.org/growl/-/growl-1.10.5.tgz",
+      "integrity": "sha512-qBr4OuELkhPenW6goKVXiv47US3clb3/IbuWF9KNKEijAy9oeHxU9IgzjvJhHkUzhaj7rOUD7+YGWqUjLp5oSA==",
+      "dev": true
+    },
     "growly": {
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/growly/-/growly-1.3.0.tgz",
@@ -5328,45 +5240,6 @@
       "integrity": "sha1-qUwiJOvKwEeCoNkDVSHyRzW37JI=",
       "dev": true
     },
-    "har-validator": {
-      "version": "2.0.6",
-      "resolved": "https://registry.npmjs.org/har-validator/-/har-validator-2.0.6.tgz",
-      "integrity": "sha1-zcvAgYgmWtEZtqWnyKtw7s+10n0=",
-      "dev": true,
-      "requires": {
-        "chalk": "^1.1.1",
-        "commander": "^2.9.0",
-        "is-my-json-valid": "^2.12.4",
-        "pinkie-promise": "^2.0.0"
-      },
-      "dependencies": {
-        "ansi-styles": {
-          "version": "2.2.1",
-          "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-2.2.1.tgz",
-          "integrity": "sha1-tDLdM1i2NM914eRmQ2gkBTPB3b4=",
-          "dev": true
-        },
-        "chalk": {
-          "version": "1.1.3",
-          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
-          "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
-          "dev": true,
-          "requires": {
-            "ansi-styles": "^2.2.1",
-            "escape-string-regexp": "^1.0.2",
-            "has-ansi": "^2.0.0",
-            "strip-ansi": "^3.0.0",
-            "supports-color": "^2.0.0"
-          }
-        },
-        "supports-color": {
-          "version": "2.0.0",
-          "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-2.0.0.tgz",
-          "integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc=",
-          "dev": true
-        }
-      }
-    },
     "has": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/has/-/has-1.0.3.tgz",
@@ -5449,18 +5322,6 @@
         "minimalistic-assert": "^1.0.1"
       }
     },
-    "hawk": {
-      "version": "3.1.3",
-      "resolved": "https://registry.npmjs.org/hawk/-/hawk-3.1.3.tgz",
-      "integrity": "sha1-B4REvXwWQLD+VA0sm3PVlnjo4cQ=",
-      "dev": true,
-      "requires": {
-        "boom": "2.x.x",
-        "cryptiles": "2.x.x",
-        "hoek": "2.x.x",
-        "sntp": "1.x.x"
-      }
-    },
     "hex-color-regex": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/hex-color-regex/-/hex-color-regex-1.1.0.tgz",
@@ -5478,12 +5339,6 @@
         "minimalistic-crypto-utils": "^1.0.1"
       }
     },
-    "hoek": {
-      "version": "2.16.3",
-      "resolved": "https://registry.npmjs.org/hoek/-/hoek-2.16.3.tgz",
-      "integrity": "sha1-ILt0A9POo5jpHcRxCo/xuCdKJe0=",
-      "dev": true
-    },
     "homedir-polyfill": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/homedir-polyfill/-/homedir-polyfill-1.0.3.tgz",
@@ -5574,17 +5429,6 @@
         "statuses": ">= 1.4.0 < 2"
       }
     },
-    "http-signature": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/http-signature/-/http-signature-1.1.1.tgz",
-      "integrity": "sha1-33LiZwZs0Kxn+3at+OE0qPvPkb8=",
-      "dev": true,
-      "requires": {
-        "assert-plus": "^0.2.0",
-        "jsprim": "^1.2.2",
-        "sshpk": "^1.7.0"
-      }
-    },
     "https-browserify": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/https-browserify/-/https-browserify-1.0.0.tgz",
@@ -5930,25 +5774,6 @@
         "html-tags": "^1.0.0"
       }
     },
-    "is-my-ip-valid": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/is-my-ip-valid/-/is-my-ip-valid-1.0.0.tgz",
-      "integrity": "sha512-gmh/eWXROncUzRnIa1Ubrt5b8ep/MGSnfAUI3aRp+sqTCs1tv1Isl8d8F6JmkN3dXKc3ehZMrtiPN9eL03NuaQ==",
-      "dev": true
-    },
-    "is-my-json-valid": {
-      "version": "2.19.0",
-      "resolved": "https://registry.npmjs.org/is-my-json-valid/-/is-my-json-valid-2.19.0.tgz",
-      "integrity": "sha512-mG0f/unGX1HZ5ep4uhRaPOS8EkAY8/j6mDRMJrutq4CqhoJWYp7qAlonIPy3TV7p3ju4TK9fo/PbnoksWmsp5Q==",
-      "dev": true,
-      "requires": {
-        "generate-function": "^2.0.0",
-        "generate-object-property": "^1.1.0",
-        "is-my-ip-valid": "^1.0.0",
-        "jsonpointer": "^4.0.0",
-        "xtend": "^4.0.0"
-      }
-    },
     "is-number": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/is-number/-/is-number-3.0.0.tgz",
@@ -5990,12 +5815,6 @@
       "integrity": "sha1-eaKp7OfwlugPNtKy87wWwf9L8/o=",
       "dev": true
     },
-    "is-property": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/is-property/-/is-property-1.0.2.tgz",
-      "integrity": "sha1-V/4cTkhHTt1lsJkR8msc1Ald2oQ=",
-      "dev": true
-    },
     "is-regex": {
       "version": "1.0.4",
       "resolved": "https://registry.npmjs.org/is-regex/-/is-regex-1.0.4.tgz",
@@ -6729,13 +6548,13 @@
       "dev": true
     },
     "js-yaml": {
-      "version": "3.6.1",
-      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.6.1.tgz",
-      "integrity": "sha1-bl/mfYsgXOTSL60Ft3geja3MSzA=",
+      "version": "3.13.0",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.0.tgz",
+      "integrity": "sha512-pZZoSxcCYco+DIKBTimr67J6Hy+EYGZDY/HCWC+iAEA9h1ByhMXAIVUXMcMFpOCxQ/xjXmPI2MkDL5HRm5eFrQ==",
       "dev": true,
       "requires": {
         "argparse": "^1.0.7",
-        "esprima": "^2.6.0"
+        "esprima": "^4.0.0"
       }
     },
     "jsbn": {
@@ -6957,12 +6776,6 @@
       "integrity": "sha1-Hq3nrMASA0rYTiOWdn6tn6VJWCE=",
       "dev": true
     },
-    "jsonpointer": {
-      "version": "4.0.1",
-      "resolved": "https://registry.npmjs.org/jsonpointer/-/jsonpointer-4.0.1.tgz",
-      "integrity": "sha1-T9kss04OnbPInIYi7PUfm5eMbLk=",
-      "dev": true
-    },
     "jsprim": {
       "version": "1.4.1",
       "resolved": "https://registry.npmjs.org/jsprim/-/jsprim-1.4.1.tgz",
@@ -7202,9 +7015,9 @@
       "dev": true
     },
     "log-driver": {
-      "version": "1.2.5",
-      "resolved": "https://registry.npmjs.org/log-driver/-/log-driver-1.2.5.tgz",
-      "integrity": "sha1-euTsJXMC/XkNVXyxDJcQDYV7AFY=",
+      "version": "1.2.7",
+      "resolved": "https://registry.npmjs.org/log-driver/-/log-driver-1.2.7.tgz",
+      "integrity": "sha512-U7KCmLdqsGHBLeWqYlFA0V0Sl6P08EE1ZrmA9cxjUE0WVqT9qnyVDPz1kzpFEP0jdJuFnasWIfSd7fsaNXkpbg==",
       "dev": true
     },
     "log-symbols": {
@@ -7820,12 +7633,6 @@
       "integrity": "sha512-T5GaA1J/d34AC8mkrFD2O0DR17kwJ702ZOtJOsS8RpbsQZVOC2/xYFb1i/cw+xdM54JIlMuojjDOYct8GIWtwg==",
       "dev": true
     },
-    "oauth-sign": {
-      "version": "0.8.2",
-      "resolved": "https://registry.npmjs.org/oauth-sign/-/oauth-sign-0.8.2.tgz",
-      "integrity": "sha1-Rqarfwrq2N6unsBWV4C31O/rnUM=",
-      "dev": true
-    },
     "object-assign": {
       "version": "4.1.1",
       "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
@@ -8551,21 +8358,6 @@
       "integrity": "sha512-uB80kBFb/tfd68bVleG9T5GGsGPjJrLAUpR5PZIrhBnIaRTQRjqdJSsIKkOP6OAIFbj7GOrcudc5pNjZ+geV2g==",
       "dev": true
     },
-    "pinkie": {
-      "version": "2.0.4",
-      "resolved": "https://registry.npmjs.org/pinkie/-/pinkie-2.0.4.tgz",
-      "integrity": "sha1-clVrgM+g1IqXToDnckjoDtT3+HA=",
-      "dev": true
-    },
-    "pinkie-promise": {
-      "version": "2.0.1",
-      "resolved": "https://registry.npmjs.org/pinkie-promise/-/pinkie-promise-2.0.1.tgz",
-      "integrity": "sha1-ITXW36ejWMBprJsXh3YogihFD/o=",
-      "dev": true,
-      "requires": {
-        "pinkie": "^2.0.0"
-      }
-    },
     "pirates": {
       "version": "4.0.1",
       "resolved": "https://registry.npmjs.org/pirates/-/pirates-4.0.1.tgz",
@@ -9322,12 +9114,6 @@
       "integrity": "sha1-fjL3W0E4EpHQRhHxvxQQmsAGUdc=",
       "dev": true
     },
-    "qs": {
-      "version": "6.3.2",
-      "resolved": "https://registry.npmjs.org/qs/-/qs-6.3.2.tgz",
-      "integrity": "sha1-51vV9uJoEioqDgvaYwslUMFmUCw=",
-      "dev": true
-    },
     "querystring": {
       "version": "0.2.0",
       "resolved": "https://registry.npmjs.org/querystring/-/querystring-0.2.0.tgz",
@@ -10324,15 +10110,6 @@
         }
       }
     },
-    "sntp": {
-      "version": "1.0.9",
-      "resolved": "https://registry.npmjs.org/sntp/-/sntp-1.0.9.tgz",
-      "integrity": "sha1-ZUEYTMkK7qbG57NeJlkIJEPGYZg=",
-      "dev": true,
-      "requires": {
-        "hoek": "2.x.x"
-      }
-    },
     "source-list-map": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/source-list-map/-/source-list-map-2.0.1.tgz",
@@ -10745,12 +10522,6 @@
         "safe-buffer": "~5.1.0"
       }
     },
-    "stringstream": {
-      "version": "0.0.6",
-      "resolved": "https://registry.npmjs.org/stringstream/-/stringstream-0.0.6.tgz",
-      "integrity": "sha512-87GEBAkegbBcweToUrdzf3eLhWNg06FJTebl4BVJz/JgWy8CvEr9dRtX5qWphiynMSQlxxi+QqN0z5T32SLlhA==",
-      "dev": true
-    },
     "strip-ansi": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/strip-ansi/-/strip-ansi-3.0.1.tgz",
@@ -11118,12 +10889,6 @@
       "integrity": "sha1-oVe6QC2iTpv5V/mqadUk7tQpAaY=",
       "dev": true
     },
-    "tunnel-agent": {
-      "version": "0.4.3",
-      "resolved": "https://registry.npmjs.org/tunnel-agent/-/tunnel-agent-0.4.3.tgz",
-      "integrity": "sha1-Y3PbdpCf5XDgjXNYM2Xtgop07us=",
-      "dev": true
-    },
     "tweetnacl": {
       "version": "0.14.5",
       "resolved": "https://registry.npmjs.org/tweetnacl/-/tweetnacl-0.14.5.tgz",
diff --git a/package.json b/package.json
index d9c6d9c..35edb54 100644
--- a/package.json
+++ b/package.json
@@ -37,7 +37,7 @@
     "@babel/runtime": "^7.4.0",
     "babel-eslint": "^10.0.1",
     "babel-loader": "^8.0.5",
-    "coveralls": "^2.13.1",
+    "coveralls": "^3.0.3",
     "enzyme": "^2.8.2",
     "eslint": "^4.0.0",
     "eslint-plugin-jest": "^20.0.3",