fix: package.json & .snyk to reduce vulnerabilities

The following vulnerabilities are fixed with a Snyk patch:
- https://snyk.io/vuln/npm:hoek:20180212

Latest report for alorel/heroku-cors-proxy:
https://snyk.io/test/github/alorel/heroku-cors-proxy

.snyk

@@ -0,0 +1,22 @@
+# Snyk (https://snyk.io) policy file, patches or ignores known vulnerabilities.
+version: v1.12.0
+ignore: {}
+# patches apply the minimum changes required to fix a vulnerability
+patch:
+  'npm:hoek:20180212':
+    - shrink-ray-current > node-zopfli > node-pre-gyp > hawk > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > hawk > boom > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > hawk > sntp > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > hawk > cryptiles > boom > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > request > hawk > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > request > hawk > boom > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > request > hawk > sntp > hoek:
+        patched: '2018-06-19T05:23:31.503Z'
+    - shrink-ray-current > node-zopfli > node-pre-gyp > request > hawk > cryptiles > boom > hoek:
+        patched: '2018-06-19T05:23:31.503Z'

package.json

@@ -11,7 +11,9 @@
   "scripts": {
     "test": "cross-env LOG_LEVEL=emerg nyc mocha -r mocha-setup.js --timeout 20000 --globals \"expect assert request\" -c ./server/**/*.spec.js ./server/*.spec.js",
     "reinstall": "rm -rf node_modules package-lock.json && npm install",
-    "start": "node server/index.js"
+    "start": "node server/index.js",
+    "snyk-protect": "snyk protect",
+    "prepare": "npm run snyk-protect"
   },
   "repository": {
     "type": "git",
@@ -35,7 +37,8 @@
     "request": "^2.83.0",
     "shrink-ray-current": "^2.1.0",
     "throng": "^4.0.0",
-    "winston": "^2.4.0"
+    "winston": "^2.4.0",
+    "snyk": "^1.83.0"
   },
   "devDependencies": {
     "chai": "^4.1.2",
@@ -45,5 +48,6 @@
     "mocha": "^5.0.0",
     "nyc": "^12.0.1",
     "supertest": "^3.0.0"
-  }
+  },
+  "snyk": true
 }