Renamed SDL_RenderPoint() and SDL_RenderLine() to SDL_RenderDrawPoint() and SDL_RenderDrawLine().
Added API for rectangle drawing (as opposed to filling)
Added placeholder API functions for circles and ellipses ... I'm not sure whether these will stay.
Optimized software line drawing quite a bit.
Added support for Wu's anti-aliased line drawing, currently disabled by default.

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%404346