1. Made the telnet thing work a bit better. It still will not work reliably to
a real telnetd on port 23.
2. Allowed network logins on client by specifying login instead of call.
3. made msg handling more robust (PC30 with unknown streams cause PC42), queueing
is only done on channels that are in state 'normal'.
4. Added pc command which takes a callsign and some text and sends it without
mods to the callsign, useful for sending manual PC protocol to unstick things.
Also for sending anonymous messages to online users.
5. Stopped duplicate messages being stored (it receives them and then bins them)
6. Implemented PC49 delete/full from outside