Correctly interleave ogg packets per granule
and set eos correctly, 2 packets buffering is needed.
It duplicates interleave_per_dts a bit,
if someone has a good solution, I'll implement it.
Originally committed as revision 11867 to svn://svn.ffmpeg.org/ffmpeg/trunk
patch by: Björn Axelsson, bjorn d axelsson a intinor d se
thread: [PATCH] Remove static ByteIOContexts, 06 nov 2007
Originally committed as revision 11071 to svn://svn.ffmpeg.org/ffmpeg/trunk