fix: package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/npm:hoek:20180212
- https://snyk.io/vuln/npm:lodash:20180130

Latest report for salty-pig/salty-pig:
https://snyk.io/test/github/salty-pig/salty-pig

package.json

@@ -19,7 +19,7 @@
     "joi": "^8.4.2",
     "lodash": "^4.13.1",
     "mongodb": "^2.1.18",
-    "node-gcm": "^0.14.3",
+    "node-gcm": "^1.0.0",
     "node-uuid": "^1.4.7",
     "stream-to-array": "^2.3.0"
   },