rbot-remote: allow override of function

[rbot] / TODO

o if searchquote (or similar) has 3 results, roundrobin between them as
asked, don't respond a random one
o freeze/thaw factoids (make them readonly) at higher auth
o respond to insults
o feed back errors from plugins (optional)
o Allow users to leave messages to named users.
o wtf plugin (bsdgames)