Snapdragon2D is now just Snap2D - Complete refactoring

-Refactored Snap2D classes and documentation to reference the library
as Snap2D rather than Snapdragon2D.  Avoiding trademark issues with
Qualcomm + it sounds better IMO.
-Reworked 'light' package and implemented system in GLHandle to use it.
-Renamed bg.x2d.anim.GTDEngine -> GTDAnimator
-Fixed bg.x2d.util.Utils making references to Snap2D
-Minor bug fixes in OpenGL renderer