add message for a particular configuration error
change irc messages to use square brackets [ ] instead of angle brackets < >

this was requested by someone whose irc client renders html 😐
don't show nickname in irc for WA messages starting with '!' or '.'

this is so that bots can parse commands from WA. Our bots
expect commands to start with '.' or '!'
fix a bug where messages starting with ':' caused an error