using glx pbuffers (with a useful debug code to display rendered
  surface into window drawable)
- better cubetextures
- split utilities functions into utils.c and added more
- more readable debug again
- a better caps code (not perfect but i'll use glx code later)
- use of the new caps code
- begin of UpdateTexture
- begin of Cursor support
- cleaning most of deprecated #if 0/#endif
- correct some lockable/unlockable behavior
- correct some returns code