Removed the last vestiges of the old code that saved the chat logs to a SQLite DB.

I'm going to develop a model to keep track of separate conversations and individuals
which will be where I keep any chat histories.
Removed old 'help message' stub and functions for individual response types.  Added conversation tracker.
Forgot to have the Conv object keep track of the log index for the individuals and their locations.
Added a simple utility model which makes a conversation dump and also makes the bot exit.
The architecture is being moved toward dynamic models.

The main bot object now keeps a list of models that have been registered
and cycles through those models with every incoming message.
Major changes.  I've pushed back the IRC interface into its own object.

I think what I'm doing is a bit kludgy and I'll probably change things around
yet again at some future point.  It's definitely better than what I was doing
before.
Merge branch 'develop'