* qatar/master:
  vsrc_buffer: allow buffering arbitrary number of frames.
  vf_scale: avoid a pointless memcpy in no-op conversion.
  avfiltergraph: try to reduce format conversions in filters.
  avfiltergraph: add an AVClass to AVFilterGraph on next major bump.
  id3v2: fix skipping extended header in id3v2.4

Conflicts:
	libavfilter/vf_scale.c
	libavfilter/vsrc_buffer.c
	libavformat/id3v2.c

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