Fix inverted textures (and hence weird kerning)
Add progress/reference screenshots
Add PrintToVBO method that takes a processed text instead of a string
Add some benchmark code to test processed vs. unprocessed text
Re-enabled drawing of main text segment using VBO's
Flip in Y direction - hack needed for correct rendering of fonts.

Possibly a better fix would be to re-order the vertex and texture
specifications in RenderGlyph()