I fixed the stereoscopic 3D to make it VR

The single-pass stereoscopic 3D in OpenGL mode should now perfectly match the values returned from the Oculus SDK (and ignore the separation and convergence values) if you select the "Oculus" stereo mode. It is tested on DK1 and DK2, but should work on other Oculus HMDs. OpenGL should now be the backend of choice for most people.

Also I merged master which had a few conflicts.