Original commit message from CVS:
* ext/ffmpeg/gstffmpegcodecmap.c: (gst_ffmpeg_codecid_to_caps):
Clarify some CODEC_ID <=> mime type conversions for image formats.
* ext/ffmpeg/gstffmpegdemux.c: (gst_ffmpegdemux_register):
Cleanup on demuxer registration.
Bumped flv demuxer to RANK_MARGINAL since it proved solid enough.
Will have to go over more demuxers, for which we don't have any
gst-plugins-* alternative, to figure out which ones can move to
RANK_MARGINAL too.