Remove methods for creating bitmaps
Remove methods for creating bitmaps

These methods made sense in Momo 1 under Canvas 2D, as they were
expensive operations, and caching them was ideal. However, in Momo 2
under WebGL, caching these types of bitmaps is no longer necessary, and
drawing them in real time is more than fast enough. As a result, I have
decided to remove both of them.

ecj2/momo