TODO

- High priority:
Refactor/cleanup conncheck.c and discovery.c
Add a nice_agent_create_source()
Implement SIP-style forking
nice_socket_recv returns -1 means we must close the nice_socket and stop all connchecks/candidates and reelect if was eleected...
Bytestream mode (non packetized) for standard ICE-TCP
Standard (RFC 6062) TURN-TCP
Server reflexive candidates for ICE-TCP (aka STUN TCP)
Clear unused local sockets (freeing file descriptions in the process) on READY
TCP simultaneous-open (S-O)

- Low priority:
Add HTTP Digest support
check for the cookie and act accordingly for incoming messages.