- Applied Tesseract's patch for drawimage extensions.  (Extended icon support and maximum width/height.)
- Added vid_asyncblit for Linux and OS X.  It defaults to true and sets SDL_AYNCBLIT on the frame buffer.  This allows for ZDoom to obtain ~100% CPU usage with an uncapped frame rate on Linux like it should.  (Not sure if it does anything for OS X yet.)  It also makes uncapped play smoothly for me (as long as the frame rate is >= 2*refresh rate), but I'm not sure if capped feels more jittery or not.  I could use some feedback here.  Do note that vid_asyncblit requires a restart after the value is changed.