#397 allow the use of real database engines

[Neurophyre]

We have had our markov database corrupted a number of times using the default (blank) configuration for supybot.databases.

We'd like to use a real database engine such as Postgres, MySQL or even SQLite as opposed to one that becomes corrupt every couple of weeks for no apparent reason.

[James McCoy]

There's work being done on converting all of Supybot's db-using plugins to have SQLAlchemy backends (dev/databases branch in git). This will allow you to use whichever database you want, as long as SQLAlchemy supports it. There are core changes that have to happen to Supybot before that can be shipped (dev/unicode branch in git).