Supervisord and celery for imap tasks
explicit int. For virtuoso but will not hurt postgres
XPUB is not helpful here. Also subscribe.
minor columnar adjustments
obtain metadata through a function. allows using schemas someday.
Merge branch 'develop' of https://github.com/ImaginationForPeople/assembl into virtuoso
The branches are now nearly identical.

Conflicts:
	assembl/lib/sqla.py
	assembl/synthesis/models.py
	assembl/tests/plugins.py
	requirements.txt
	supervisord.conf