a lot of stuff in here around support for loading plugins from arbitrary
files. plugins have a basic amount of initialization and then hook into
the core IRC event system
it makes sense to have modules respond to regexes, so there's some
handler stuff for that --- it was the most popular way to do stuff in
the old version of the bot
we need to check that people trying to load plugins are admins, so
there's some stuff for that, too
the expectation is that many features from here are happen in plugins,
rather than modifying the core bot
