API changes, most recent first:
+2017-09-27 - xxxxxxx - lavu 55.77.101 / lavu 55.31.1 - frame.h
+ Allow passing the value of 0 (meaning "automatic") as the required alignment
+ to av_frame_get_buffer().
+
+2017-09-27 - xxxxxxx - lavu 55.77.100 / lavu 55.31.0 - cpu.h
+ Add av_cpu_max_align() for querying maximum required data alignment.
+
2017-09-26 - xxxxxxx - lavc 57.106.102 - avcodec.h
Deprecate AVCodecContext.refcounted_frames. This was useful for deprecated
API only (avcodec_decode_video2/avcodec_decode_audio4). The new decode APIs