[#167] fixed `grunt clean` not removing "docs/styles"
[#167] fixed `grunt clean` not removing "docs/styles"

Smoss/Enoru-eco,srbala/melonJS,rlugojr/melonJS,MarkoIvanetic/melonJS,rlugojr/melonJS,gopalindians/melonJS,melonjs/melonJS,melonjs/melonJS,rlugojr/melonJS,TukekeSoft/melonJS,srbala/melonJS,gopalindians/melonJS,gopalindians/melonJS,MarkoIvanetic/melonJS,Smoss/Enoru-eco,TukekeSoft/melonJS,TukekeSoft/melonJS,srbala/melonJS