Optimize Spritebatch

[LunaTheFoxgirl]

the opengl spritebatcher could be optimized further, since the current layout for the VBO is very simplistic (AND SLOW), I will be pushing a project to the polyplexengine org with a particle stresstest later, which can be used to test optimzations of 2D.

Working on it on the optim-spr branch.
Todo List:

• Optimize data types used for VBO.
• Use IBO.
• Use double buffer VBO.
• Add draw bucketing and sorting