support joining irc channels with keys
throttle really long streams of messages
- barring real absurd cases i think the best way to do this would
  be to cut off any more than N (say ten) messages sent to a channel
  within any timespan (say, a second)
  commands with a lot of output (1000 lines, say) will probably be processed
  by the queue fast enough to just get rid of them
  this isn't the best possible system but it will work
reasonable interop between unicode and non-unicode
- we can just send bytes as-is, but i think this is unwise. we can
  *accept* bytes as is, which is fine i think, and then make non-
  unicode bytes turn into their unicode counterparts