Use OpenHMD provided proj/view matrix #15

Ohai!

I was playing around with VRZero a bit and realized that it only uses the rotational information from OpenHMD.
By using the provided Projection and View matrices, you will get correct rotation and position information, while also getting IPD and some lens information for more correct rendering.

As OpenHMD is getting more positional devices, and Raspberry Pi's are getting better specs, My goal is to get the current DK2/CV1 positional tracking (https://github.com/thaytan/OpenHMD/tree/rift-kalman-filter) working on Pi4. If the projection and view matrices are used, that tracking would work out of the box with VRZero, which would be great for demo's and prototyping!

Thanks