Added a sphere method to Object.  Currently it just generates an icosahedron, but later I'm going to add in tesselation so that it can be a real sphere.

Currently you can't rotate the sphere because that seems kinda pointless, but I may add that in later as it could be useful for low-poly spheres.
Merge branch 'master' of https://github.com/jayelliott/geomorph

Conflicts:
	Object.cpp
	Object.h
	Scene.h
	SceneParser.cpp
	SceneParser.h

Yeeeeahhhh, sometimes I do two separate things in two separate working copies and then this happens and I have to go fix it.