Merge commit 'b7f1010c'

* commit 'b7f1010c':
  tools: do not use av_pix_fmt_descriptors directly.
  pixdesc: add functions for accessing pixel format descriptors.
  build: add support for Tru64 (OSF/1)
  md5: Allocate a normal private context for the opaque md5 context pointer

Conflicts:
	cmdutils.c
	doc/APIchanges
	ffprobe.c
	libavformat/md5enc.c
	libavutil/version.h
	tools/graph2dot.c

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