I'm not sure if there's a bug in mesa, or if I'm doing something wrong, but
GL_POINTS doesn't seem to be working properly. I get the points, but
writing to gl_PointSize doesn't make a difference despite the size range
being 1-255.
Unfortunately, the maximum point size on Intel hardwar seems to be 1, so I
can't tell if the colors are right.
This is largely just a hacked version of GL's particle code.
Add GLSL directory to QF and use it for all gsls based code (instead of
GL). defines.h, types.h and funcs.h are derived from gl2.h from khronos.
Text drawing now uses triangles instead of quads.
