update the uglify grunt task version
update the uglify grunt task version

minification information is finally back -> `File build/melonJS-min.js
created: 911.13 kB → 208.51 kB`

melonjs/melonJS,melonjs/melonJS,rlugojr/melonJS,rlugojr/melonJS,rlugojr/melonJS