chore(package): update mocha to version 2.3.4

http://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -61,7 +61,7 @@
     "dekeywordify": "0.2.1",
     "eslint": "1.9.0",
     "istanbul": "0.4.0",
-    "mocha": "2.3.3",
+    "mocha": "2.3.4",
     "npm-run-all": "1.2.13",
     "uglifyify": "3.0.1",
     "utf8-length": "0.0.1",