Starling Performance Enhancements

I had previously written some performance tests comparing ND2D and Starling with each other. Starling seemed to lag behind quite significantly. Since then the library has seen a couple of performance enhancements. I've posted some new tests below using Starling 0.9.1. It's still slightly slower (especially as ND2D is automatically smoothing the bitmaps) but the changes have definitely brought it up to a respectable speed. I had to increase the amount of sprites from 2000 to 10000 to be able to see the difference.