Add some braces to make this code clearer.
Add several missing debug flags to config loader.
Implement print_shader_source for non-ARB.
Remove lightCam from XToon shader uniforms.

The shader compiler optimizes it out since it's not used for anything,
and then the main program can't find it.
Remove reserved word output in Painterly shader.
Add newer GL versions to GLEW debug info.
Remove unused ratio_scale from blur shader.
Use FBOs instead of the AUX buffer where available.

I'm not sure whether or not this achieves anything, but it stops OpenGL
from throwing an error (that probably cascades since errors are not
checked too often).
Clean up GLSL shaders.

Remove commented code, re-indent stuff, etc.