API changes, most recent first:
+2015-xx-xx - xxxxxxx - lavf 56.20.0 - avio.h
+ Add avio_put_str16be.
+
+2015-xx-xx - xxxxxxx - lavu 54.14.0 - cpu.h
+ Add AV_CPU_FLAG_AVXSLOW.
+
+2015-xx-xx - xxxxxxx - lavc 56.23.0
+ Add av_vda_default_init2.
+
2015-xx-xx - xxxxxxx - lavu 54.12.0
Add AV_LOG_TRACE for extremely verbose debugging.