chore(package): update mocha to version 3.2.0

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -25,7 +25,7 @@
     "codecov": "1.0.1",
     "eslint": "3.10.2",
     "istanbul": "0.4.5",
-    "mocha": "3.1.2"
+    "mocha": "3.2.0"
   },
   "scripts": {
     "test": "make lint && make coverage"