fixed stupid bug in q1bsp texture loading which was making all missing textures invisible
changed portal generation to not break when a portal is clipped away, this fixes a crash at render time with bogus portals
changed r_drawportals to only draw portals surrounding the visible leafs (speed gain, but also useful for debugging vis glitches)
git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@5153
d7cf8633-e32d-0410-b094-
e92efae38249