- patch a reference picture leak in ffmpeg/libavcodec/mpegvideo.c that caused aborts...

 - patch a reference picture leak in ffmpeg/libavcodec/mpegvideo.c that caused aborts on h264 transport stream encodes.
 - patch the log level of some h264 decoder error messages so we don't fill our log with messages about stuff that's a very likely & not terribly significant.
 - don't let hb.c set the ffmpeg av_log level to AV_LOG_DEBUG -- it fills the HB activity log with junk.
 - add a count of the decoder errors to decavcodec's final report.
 - when we don't have any chapter text (i.e., during a typical cli encode) just print the chapter number rather than empty quote marks.

git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@1639 b64f7644-9d1e-0410-96f1-a4d463321fa5