More Quadtree testing

The buffer building is way too slow, I'm going to try using multiple
selective draw calls instead of rebuilding the buffer every frame.
Initial work on fractal heightmap generation
Added the Tile class for terrain (NYI)
Implemented Tile system in FractalTerrainRenderer
Added a temporary FPS counter
Added SkyBox renderer to replace SkySphere
Improved fractal terrain

Fixed axis alignment
Added new AxisRenderer