Blender Git Loki

fix for recent stereo changes+tweaks
(it's the 3rd commit in a row. But as they say, the 3rd is always a charm ;)

I still think we have a little mess with the DEFINE parameters in BGE (as in RAS_IRasterizer::StereoMode).
We used to have them duplicated and hardcoded in 2.4xx, but I think we can do it in another way now.

(I didn't change gameplayer, but I can do it once we have it linking and building properly)