chore(package): update mocha to version 4.0.1

Closes #62

Author: greenkeeper[bot]

package.json

@@ -51,7 +51,7 @@
     "swint-yuidoc": "1.0.10"
   },
   "devDependencies": {
-    "mocha": "3.5.3",
+    "mocha": "4.0.1",
     "eslint": "4.7.0",
     "request": "2.81.0"
   }