Update to SDL_image snapshot 2013-08-08 (rev 420).
Update to SDL_mixer snapshot 2013-08-08 (rev 656).
Update to SDL_net snapshot 2013-08-08 (rev 249).
Update to SDL_ttf snapshot 2013-08-08 (rev 253).
Rebuild the correct revision this time.

I didn't notice that the fetch.sh run failed so the last build packaged
up the old version.  Oops.
Remove docs.patch (no longer necessary).