Update logging and default settings.

Restore the __main__ block in web.py as runserver is complicating
getting log messages out.
Start trying to fix logging config and use gunicorn instead.
Update requirements.txt
Remove __main__ block as webserver uses gunicorn now.
Update sample configuration.
Fix logging hell.

disable_existing_loggers=False allows config to update loggers
that may already exist. This makes life much simpler for me.
Remove runserver.py it didn't contribute much.

It also serves no point with gunicorn in place.
Update celery config