Having two buffers for audio isn't really good.
Make the maximum size of the jbuf at least 4 times the capacity.

Should prevent issues that might occur because a different thread is
reading it.
Increase video quality and distance between keyframes.
Fixed a memory leak
Fixed memory leaks.
Merge branch 'mem-leak-fix' of https://github.com/nurupo/InsertProjectNameHere
More group auto testing.
Sendback data size is always 8 bytes.
Fixed DHT doc.
Increased max TCP connections.
Some optimizations on how TCP relays are used.
DHT fixes.

This should speed up DHT searches.
Fixed test.
cs_set_video_encoder_resolution improvements.
Fixed some A/V threading issues.

Audio dropping on video calls issue should no longer happen.
Cut one on one default audio bitrate by half.
Build system fixes.

libtoxcore.pc now has -lpthread like it's supposed to on systems
where it is needed.