Fix XCode build, fixes #101
Some fixes for the tty client
Use NullAudio for the TTY client
Fix the build
Don't link OpenAL into tty client and don't include NullAudio in dedicated server
Properly handle www downloads being interrupted by a disconnect
Add preset for hw such as Intel GMA 3xxx/4xxx
Fix bound check in SetReverb
Make CvarSystem use auto& to iterate over cvars

Also do some cosmetic changes (docs, ...)
Fix cvars not being reset properly when sv_cheats is set to 0
Merge branch 'master' into bullet
Tell travis to use Bullet
Travis doesn't have bullet, prevent it from compiling the bullet branch for now
Bullet: WIP, more debug, split convex hull tesselation
Bullet: use CGAL instead of the approximate bullet convex hull to triangle converter