chore(package): update coveralls to version 2.11.5

http://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -59,7 +59,7 @@
   },
   "devDependencies": {
     "concat-stream": "^1.5.0",
-    "coveralls": "^2.11.4",
+    "coveralls": "^2.11.5",
     "istanbul": "^0.4.0",
     "jshint": "^2.8.0",
     "mocha": "^2.3.4",