Seems like glitches in the code

[ravenrani]

[1] It seems like the DatagramSockets are not being closed properly.
I tried fixing some issues, by adding reusable address, and finally with socket.close
However some Address already in use issues are still happening.
[2] There are timeouts while receiving the STUN answer, not sure why those happen, but they are finished with unknown
[3] I am not sure how the ports are being picked, I believe it should have been done by the webrtc candidates selection or similar.
It seems that different codes trying to mimic the same thing are using different default ports, os I am not sure.
[4] It seems like part of the algorithm to distinct between nat-types is supposed to be using at least 2 different STUN servers