Blender Git Loki

GPU: bind builtin shader for immediate mode

immBindBuiltinProgram extends Gawain?s immBindProgram to use Blender?s
library of built-in shader programs.

It uses imm prefix instead of GPU_ so people won?t be tempted to call
GPU_unbind_program() afterward.

From my understanding, Apache code is not allowed to call GPL code, so
this function needs to be in the GPU lib.