*Added VisibilityController
*also updated index.html to load this controller
Merge branch 'master' of https://github.com/GameMechanicsSociety/angrybox

# By laykun
# Via laykun
* 'master' of https://github.com/GameMechanicsSociety/angrybox:
  changed the default plane of existence
  Changed gravity axis. Fixed up lots of bugs.

Conflicts:
	public/worldcontroller.js