markov targets are queried and autogenerated based on chatter, but had a
legacy name which is no longer in use for this, preferring the foreign
keys to channel and consequently server. the name is really just
informative these days, but was still being used to find targets, and
thus was breaking when two servers had the same channel name in them.
this fixes that
this is just a basic port of the tables into django models right now.
there's some serious slowness in the state creation that i need to fix
before this does anything, but i want to get this in a real database on
a real linode before i go too much further, so here it is
