chore(package): update grunt-contrib-clean to version 1.1.0

https://greenkeeper.io/

Author: greenkeeperio-bot

package.json

@@ -25,7 +25,7 @@
     "grunt-browserify": "5.0.0",
     "grunt-bump": "0.8.0",
     "grunt-cli": "1.1.0",
-    "grunt-contrib-clean": "1.0.0",
+    "grunt-contrib-clean": "1.1.0",
     "grunt-contrib-compress": "1.4.1",
     "grunt-contrib-concat": "1.0.1",
     "grunt-contrib-connect": "1.0.2",