Add fine-grained debug layer

Full GLES error checking layer via -include
trickery. Change DEBUG_OPENGL to a level system.

HIGH = every GL call is error checked
MODERATE = checkpointing at interesting spots
LOW = only asserts there are no errors at the end of a frame
 or when the FBO changes
NONE = AIN'T GOT NO TIME FOR ERRORS GOTTA GO FAST!

Change-Id: Ibe81aae93d942059c4ddf1cbb11c828b7ce4c10b