chore(package): update ember-cli to version 3.1.4

Closes #237

Author: greenkeeper[bot]

package.json

@@ -26,7 +26,7 @@
     "babel-eslint": "^8.0.1",
     "broccoli-asset-rev": "^2.6.0",
     "ember-ajax": "^3.0.0",
-    "ember-cli": "2.13.2",
+    "ember-cli": "3.1.4",
     "ember-cli-app-version": "^3.1.0",
     "ember-cli-blanket": "0.9.10",
     "ember-cli-chai": "^0.4.3",