Fix Oculus VR support

Feedback welcome.

The Euler angles appeared to be in the wrong order, everything seems to be working fine now.

The yaw/pitch/roll can be problematic while using the Rift, and given the interdependence of Euler angles it can create some pretty funky results at the thresholds.  I assume they are there to limit the rotation from the POV of another user, but ideally the camera would have full freedom even if the avatar's rotations are limited.  Maybe this is already the case, I haven't dug into the code enough to have a full view of how everything works.