[FFmpeg-cvslog] Changelog: add 2.8

ffmpeg | branch: master | Michael Niedermayer | Sun Sep 6 15:59:23 2015 +0200| [c5406d5e150344f8aea092afd6d9e552b3be1ac9] | committer: Michael Niedermayer Changelog: add 2.8 Signed-off-by: Michael Niedermayer > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c5406d5e150344f8aea092

[FFmpeg-cvslog] Changelog: Add 2.8

ffmpeg | branch: release/2.8 | Michael Niedermayer | Sun Sep 6 16:00:01 2015 +0200| [90d29c3d048fdfc2ee3e566e26ee58b1d848bdbd] | committer: Michael Niedermayer Changelog: Add 2.8 Signed-off-by: Michael Niedermayer > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=90d29c3d048fdfc2e