move some global members of tc_client to BuddyList

TOR_CONFIG
tor_pid
tor_proc
tor_timer
startPortableTor()
stopPortableTor()
startPortableTorTimer()
onPortableTorTimer()
listen on random free port if port=0

* tor_portable.socks_port
* client.port
check existance of wx_ctrl in Control.setEnabled

fix attribute error in subclass Check
add config item turning account into chat room

additional config item is to prefer nicks over torchat ids
remove debugging print
do not allow nicks looking like addresses in chats

move isValidAddress to global tc_client's namespace
reported user agent can be changed in preferences

allow UTF-8 in user agent