feat(#31): Upgrade NPM dependencies

BREAKING CHANGE

 - Upgrading major version of Mocha

package.json

@@ -1,6 +1,6 @@
 {
   "name": "jenkins-mocha",
-  "version": "5.0.0",
+  "version": "6.0.0",
   "description": "Bin wrapper for Mocha + Nyc + Xunit (for Jenkins)",
   "bin": {
     "jenkins-mocha": "./bin/jenkins.js"
@@ -26,18 +26,18 @@
   "bugs": "https://github.com/stjohnjohnson/jenkins-mocha/issues",
   "license": "MIT",
   "dependencies": {
-    "mocha": "^3.0.0",
+    "mocha": "^4.0.0",
     "npm-which": "^3.0.0",
     "nyc": "^11.0.0",
     "shell-escape": "^0.2.0",
     "shelljs": "^0.7.5",
     "spec-xunit-file": "0.0.1-3"
   },
   "devDependencies": {
-    "chai": "^3.0.0",
-    "coveralls": "^2.11.15",
+    "chai": "^4.0.0",
+    "coveralls": "^3.0.0",
     "mockery": "^2.0.0",
-    "sinon": "^1.10.3"
+    "sinon": "^4.0.0"
   },
   "release": {
     "debug": false,