Nouveau/headers

Wrote a script to simply sync the headers from nvidias public doc repository

We shouldn't write our own ones :)

We got 2D, COPY, M2MF and compute which should be good enough for now.

There are also video headers, but without the firmware it's pain to use them.

We should get 3D and P2MF (latter used on kepler) from nvidia as well so we have everything used by the current GL driver.