Merge pull request #2 from grayyang/greenkeeper/coveralls-3.0.0

Update coveralls to the latest version 🚀

Author: grayyang

package.json

@@ -33,7 +33,7 @@
   "devDependencies": {
     "chai": "^4.1.1",
     "chai-as-promised": "^7.1.1",
-    "coveralls": "^2.13.1",
+    "coveralls": "^3.0.0",
     "eslint": "^4.4.1",
     "js-promisify": "^1.1.0",
     "mocha": "^4.0.0",