Complete TCP/UDP support

[mkapal]

As per the InSim.txt spec:

// NOTE 1) UDPPort field when you connect using UDP:

// zero     : LFS sends all packets to the port of the incoming packet
// non-zero : LFS sends all packets to the specified UDPPort

// NOTE 2) UDPPort field when you connect using TCP:

// zero     : LFS sends NLP / MCI packets using your TCP connection
// non-zero : LFS sends NLP / MCI packets to the specified UDPPort