Merge pull request #32 from ember-fastboot/greenkeeper/mocha-4.0.0

Update mocha to the latest version 🚀

Author: rwjblue

package.json

@@ -32,7 +32,7 @@
     "chai-as-promised": "^7.1.1",
     "ember-cli": "^2.7.0",
     "express": "^4.13.4",
-    "mocha": "^3.4.2",
+    "mocha": "^4.0.0",
     "mocha-jshint": "^2.3.1",
     "request-promise": "^4.2.1"
   },