(and fix) stream copying. By now force_pts it's just honoured by the MPEG
muxer. ASF could honour this also, but it should be fixed to use Tickers
first.
- MPEG audio decoder exports it's frame size in bytes.
- Hope this fix the floating point exception found in ffserver.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@382 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b