Rewrote sv_user.nc

Rewrote sv_user.nc
Added support for the 'max air control' game option
The only game option not implemented is grappling hooks... not sure if we want them
Some notes about the new player physics:
- Slightly more sane default air control. Just enough to hop onto a ledge.
- sv_maxspeed is read from cvars again, not hardcoded, so be sure to set your sv_maxspeed.
- Got rid of edgefriction. It's weird.
- Should we get rid of showing roll angles on the player model? I never liked that.
- Crouching doesn't slow you down yet...

git-svn-id: svn://svn.icculus.org/nexuiz/trunk@197 f962a42d-fe04-0410-a3ab-8c8b0445ebaa