API changes, most recent first:
+2015-xx-xx - xxxxxxx - lavc 57.11.0 - avcodec.h
+ Add av_packet_add_side_data().
+
2015-xx-xx - xxxxxxx - lavc 57.9.1 - avcodec.h
Deprecate rtp_callback without replacement, i.e. it won't be possible to
get image slices before the full frame is encoded any more. The libavformat