Update uglify version
Update uglify version

Old version was causing warning on clean build due to gruntjs/grunt-contrib-uglify#315

IveWong/AlertifyJS,IveWong/AlertifyJS,xzpnuist/AlertifyJS,xzpnuist/AlertifyJS,davioliveira/AlertifyJS,AndersonFirmino/AlertifyJS,davioliveira/AlertifyJS,AndersonFirmino/AlertifyJS