Merge pull request #383 from isleofcode/greenkeeper/mocha-4.0.0

Update mocha to the latest version 🚀

Author: alexblom

package.json

@@ -81,7 +81,7 @@
     "ember-cli-shims": "^1.0.2",
     "eslint-plugin-chai-expect": "^1.1.1",
     "loaderjs": "^0.1.8",
-    "mocha": "^3.4.2",
+    "mocha": "^4.0.0",
     "mocha-eslint": "2.1.1",
     "mocha-jshint": "^2.3.1",
     "testdouble": "^3.0.0"