changed renderer to check ent->colormap_pantscolor and ent->colormap_shirtcolor inste...

changed renderer to check ent->colormap_pantscolor and ent->colormap_shirtcolor instead of ent->colormap to detect whether to use colormapping on a model, this should reduce chance of bugs in lighting code
also optimized the R_Shadow_RenderSurfacesLighting function a bit to have separate handling of colormapped and non-colormapped surfaces (probably a small speed gain, and reduces chance of bugs in lighting code)

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@5934 d7cf8633-e32d-0410-b094-e92efae38249