Powder: New PSP release!

Game by Stanislaw Skowronek, PSP porting + changes by Brian Ledbetter
Comments: irc.unaligned.org #wtf or brian@brianledbetter.com (we already know it's slow. it's complicated. it uses lots of math. ok.)

Just like any other homebrew PSP app, copy to PSP/GAME/powder folder on an M33-firmware'd PSP (runs on 3.xx kernel). Run. Follow onscreen instructions (no, seriously, they're full of useful tricks). Have tons of fun.

October 25 2008:
No more major PSP reworking. Added Fan feature and pressure/velocity display select from upstream. Might still fix vectorization but it seems to run decently fast as-is. Removing SDL (10/15) made a *huge* difference.

October 15 2008:
Now doesn't use libm or newlib, only things linked in are now the PSP stubs and SDK libc. Brings code from 250+KB with SDL, to ~120KB with newlib to <60(!)KB now. 
So more speed.
Still working on the vectorization bug, GCC is a finicky beast. -O2 and -Os mysteriously started working, both with vectors and without (before, they would just produce completely broken code in either config), -O3 works without vector (but with it, fails). -O3 produces 
faster code without the vectorization than -O2 does with, so I'm just going with -O3 and no vectorization for this release.
