doc/APIchanges: fill in missing hashes and dates
doc/APIchanges: mark the release 10 branch point
ffprobe: fix crash happening because of new streams occuring

Fix trac ticket #3603.

Signed-off-by: Stefano Sabatini <stefasab@gmail.com>
wavenc: use codec descriptors to get the codec name

Also, return a proper error code.
Merge commit '33082af7560a18179b52734665ef66f812902d33'

* commit '33082af7560a18179b52734665ef66f812902d33':
  doc/APIchanges: fill in missing hashes and dates

Conflicts:
	doc/APIchanges

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '968a62a9d9e3a785ce1f79b80facfe09c6c14544'

* commit '968a62a9d9e3a785ce1f79b80facfe09c6c14544':
  doc/APIchanges: mark the release 10 branch point

Conflicts:
	doc/APIchanges

Not merged, as there was no such branch in ffmpeg

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'd246231e4714119faac6c7acd881d3b687bb8b11'

* commit 'd246231e4714119faac6c7acd881d3b687bb8b11':
  wavenc: use codec descriptors to get the codec name

Conflicts:
	libavformat/wavenc.c

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