Preparing the tree positioning.
Merge branch 'master' of https://github.com/elib/GGJ2013

Conflicts:
	GGJ/src/GameWorld.as
	GGJ/src/Tree.as
Testing tile number 0 (bottom of screen)
Finally placed the trees on the tilemap correctly... or close enough.
Adding Layers.
Merge branch 'master' of https://github.com/elib/GGJ2013

Conflicts:
	GGJ/src/Tree.as