stripped out game.remove/removAll

#327 

Removed the me.game.remove() method. Updated documentation to use `me.game.world.removeChild`. 

@obiot wanted you to check it out first, given we should be careful on the remove function since the `me.game.remove` has the force option. Through my experience in using melon, the force is nothing really but trouble.

Testing against the different examples and some of my own it seems to be fine. The main thing is users will need to update their code to use removeChild.