* commit '252d6200':
  avio: Add avio_put_str16be

Conflicts:
	doc/APIchanges
	libavformat/avio.h
	libavformat/aviobuf.c
	libavformat/version.h

The FFmpeg implementation is kept as requested by ubitux
Doxy improvements merged
Merged-by: Michael Niedermayer <michaelni@gmx.at>