Rewrite of starting project code.
Merge branch '_util' into development
Added basic render manager.
Merge branch '_renderer' into development
Added base Scene class.
Merge branch '_scene' into development
Added basic demo scene.
Merge branch '_demo' into development
Split util.lua into a directory.
Added Vector2 class.
Added Color class.
Added some shapes and collision methods.
Moved background color and clear() to renderer.
Merge branch '_util' into development