Merge remote-tracking branch 'qatar/master'

* qatar/master:
  movenc: change AV_LOG_INFO to AV_LOG_WARNING for some warnings
  avconv: remove a write-only variable
  avconv: remove pointless parameter from new_*_stream().
  avconv: cosmetics, move code
  avconv: cosmetics -- move copy_chapters().
  avconv: cosmetics -- move parse_forced_key_frames().
  lavc: add audio flag to the 'b' option, deprecate 'ab'.
  avconv: rename sameq to same_quant
  doc/avconv: add forgotten end of chapter.
  Changelog: document avconv incompatibilities with ffmpeg.
  avconv: replace -vcodec/-acodec/-scodec with a better system.
  avconv: remove presets.
  svq3: propagate codec memory allocation failure in context init

Conflicts:
	Changelog
	avconv.c
	libavcodec/options.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>