Merge remote-tracking branch 'qatar/master'

Merge remote-tracking branch 'qatar/master'

* qatar/master: (22 commits)
  H.264: fix filter_mb_fast with 4:4:4 + 8x8dct
  alsa: limit buffer_size to 32768 frames.
  alsa: fallback to buffer_size/4 for period_size.
  doc: replace @pxref by @ref where appropriate
  mpeg1video: don't abort if thread_count is too high.
  segafilm: add support for videos with cri adx adpcm
  gxf: Fix 25 fps DV material in GXF being misdetected as 50 fps
  libxvid: Add const qualifier to silence compiler warning.
  H.264: improve qp_thresh check
  H.264: use fill_rectangle in CABAC decoding
  H.264: Remove redundant hl_motion_16/8 code
  H.264: merge fill_rectangle into P-SKIP MV prediction, to match B-SKIP
  H.264: faster P-SKIP decoding
  H.264: av_always_inline some more functions
  H.264: Add x86 assembly for 10-bit H.264 predict functions
  swscale: rename uv_off/uv_off2 to uv_off_px/byte.
  swscale: implement error dithering in planarCopyWrapper.
  swscale: error dithering for 16/9/10-bit to 8-bit.
  swscale: fix overflow in 16-bit vertical scaling.
  swscale: fix crash in 8-bpc bilinear output without alpha.
  ...

Conflicts:
	doc/developer.texi
	libavdevice/alsa-audio.h
	libavformat/gxf.c
	libswscale/swscale.c
	libswscale/swscale_internal.h
	libswscale/swscale_unscaled.c
	libswscale/x86/swscale_template.c
	tests/ref/lavfi/pixdesc
	tests/ref/lavfi/pixfmts_copy
	tests/ref/lavfi/pixfmts_crop
	tests/ref/lavfi/pixfmts_hflip
	tests/ref/lavfi/pixfmts_null
	tests/ref/lavfi/pixfmts_scale
	tests/ref/lavfi/pixfmts_vflip

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