Remove commented out code from tr_main.c to tr_world.c
Remove commented out code in the rest of the renderer
Remove remains of HDR, Deferred rendering, SSAO and DoF
Remove unused shaders and Rotoscope
Remove the COMPAT_ET COMPAT_Q3A and VOLUMETRIC_LIGHTING compile defs
Remove support for MDC, PSK and PSA
Do not check for MDS, it is not supported, thanks ZTM
Update the CMakeList for the removal of PSK and MDC
Fix IQM support being removed

Thanks ZTM for pointing out a bug in the initial commit.
Fix CGame compat