Switching BROKER_HOST to sqlite:// instead of sqlalchemy+sqlite://

Switching BROKER_HOST to sqlite:// instead of sqlalchemy+sqlite://

Okay, so if you run git master of kombu, this works.  And if you run
the older kombu + kombu-sqlalchemy, this also worked.  In the last
release of kombu (2.1.5) there's a bug, and sqlalchemy+sqlite://
worked for processes consuming tasks but not ones publishing tasks.

Aye aye aye.

I guess we might have to move our setup.py back to the old kombu +
kombu-sqlalchemy setup until they put out a new kombu release? :(