Replaces glBegin/End with glDrawArrays, GL_QUADS with GL_TRIANGLES, and
replaces glPush/PopAttrib by resetting the viewport manually.
Adjusts GLSL shaders for these changes.
This was SVN commit r14152.
Switch all the constant strings in graphics code to use the new
variables.
This avoids the cost of instantiating CStrInterns at runtime every
frame.
This was SVN commit r13906.