Fixed a limitation that was preventing a non visible layer to be set visible later
Fixed a limitation that was preventing a non visible layer to be set visible later

note that this is not applicable to collision layer, which are forced to
non visible unless the `me.debug.renderCollisionMap` flag is set

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