mov: read hydrogenaudio replaygain information
Merge commit '9a07fac678a8540d076e635061bbaa4ed09a9431'

* commit '9a07fac678a8540d076e635061bbaa4ed09a9431':
  mov: read hydrogenaudio replaygain information

Conflicts:
	libavformat/Makefile
	libavformat/mov.c

See: 37a15f3e669372075c88254e070c971aecb485aa
Merged-by: Michael Niedermayer <michaelni@gmx.at>
avformat/mov: merge mov_read_custom_metadata() and mov_read_custom()

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