Better maze generation algorithm

[McSinyx]

The current binary tree algo is flawed and retarded. The generation should be:

• Unbiased
• Varier, i.e. with big rooms and small paths, or cave-like (shape-free)

Still it need to be fast (since we'll need to regenerate every few frames) and infinite (perfect loops don't count).

[McSinyx]

Until this actually get solved, I'll try to draw the maze rotated 45° to the right to make the flaw seem to be intended.

[McSinyx]

This is really solved now.