Another update

This time I have put on SVN some NeHe's 3d examples, sound related stuff and... well, this is the changelog from SVN:

+ Added a lot of new examples from devkitPro (NeHe's 3d, sound, input, debugging, libfat)
+ Added Christmas PGD demo sources
* Fixed postest.inc, dma.inc, timers.inc
* Updated video.inc
* Fixed and updated a lot of stuff in videoGL.inc (mainly fixed point conversion and 3d funcs)
As usual, any feedback is very appreciated