out BGR8 upside-down. the workaround for this is removed.
2) fixes a bug so that streaming gifs now works, and removes a
workaround no longer needed. now libgif uses mplayer's stream_read
function and thus http streaming, etc, works with demux_gif.
3) cosmetic clean-up because i no longer plan to support certain GIF
extensions that would be more difficult to implement.
patch by Joey Parrish <joey@nicewarrior.org>
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@9345 b3059339-0415-0410-9bf9-f77b7e298cf2
