Add trivial triangle reject tests: backface culling and bounding box check. Adding backface culling speeds up rendering the torus demo by 1.7x.  Adding bounding box checks to this brings the total speedup to 6.4x.
Add trivial triangle reject tests: backface culling and bounding box check.
Adding backface culling speeds up rendering the torus demo by 1.7x.  Adding
bounding box checks to this brings the total speedup to 6.4x.

jbush001/NyuziProcessor,FulcronZ/NyuziProcessor,hoangt/NyuziProcessor,hoangt/NyuziProcessor,jbush001/NyuziProcessor,FulcronZ/NyuziProcessor,jbush001/NyuziProcessor,jbush001/NyuziProcessor,hoangt/NyuziProcessor,FulcronZ/NyuziProcessor,hoangt/NyuziProcessor,jbush001/NyuziProcessor,jbush001/NyuziProcessor,FulcronZ/NyuziProcessor