util::Image::swapRedBlue()

Added method to swap red and blue channels. This enables util::Image to
have a single format (well, a single 32-bit-per-pixel format) and still
deal with OpenGL texture format requirements. (RGBA makes R the first
byte).
Maze-like first-person shooter

As an experiment and to impress my wife, I've started a quick-and-dirty
test of the abstractions and platform. Specifically, I'm implementing a
wolfenstein3d-like video game with a maze-like environment.