Merge remote-tracking branch 'qatar/master'

* qatar/master:
  isom: sort and pretty-print codec_movaudio_tags[]
  isom: remove pointless comments in codec_movaudio_tags[]
  isom: remove commented-out tag for vorbis
  movenc: write 'chan' tag for AC-3 in MOV
  mov: add support for reading and writing the 'chan' tag
  audioconvert: add some additional channel and channel layout macros
  audioconvert: change 7.1 "wide" layout to use side surround channels
  movenc: simplify handling of pcm vs. adpcm vs. other compressed codecs
  doc: update documentation to use avconv
  doc: update demuxers section
  doc: extend external library coverage
  doc: split platform specific information
  doc: port the git-howto to texinfo
  doc: provide fallback css and customize @float
  doc: document fate in a texinfo
  doxy: change hue value to match our green

Conflicts:
	doc/fate.txt
	doc/ffserver.texi
	doc/general.texi
	doc/muxers.texi
	doc/protocols.texi
	doc/t2h.init
	libavformat/isom.c
	libavformat/mov.c
	libavutil/avutil.h
	tests/ref/acodec/pcm_s16be
	tests/ref/acodec/pcm_s24be
	tests/ref/acodec/pcm_s32be
	tests/ref/acodec/pcm_s8
	tests/ref/lavf/mov

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