Migration to SDL done

Tool doesn't use GLUT anymore to manage its display window & user events, SDL does the dirty work (http://www.libsdl.org/).

The change was rather quick, only three classes where privately affected: CWindowManager, CMouseController, and CKeyboardController.

No public interface was broken, so no other class was changed.

The change was necessary because I needed more control on the main loop, which GLUT doesn't provide.
E.g. quitting GLUT's main loop requires an exit(0), and it needed global functions for callbacks.
SDL is more complex but much cleaner (provided it's used right of course) and provides image format handling facilities, which will be necessary for textures.

So GLUT was great for a kickstart, but the change for SDL was necessary.