Don't cleanup on transaction end
Don't cleanup on transaction end

Now that zope.sqlalchemy is gone this doesn't happen anymore except
after completely processing a request - and at this point there's no
Indico code running anymore.

OmeGak/indico,ThiefMaster/indico,indico/indico,DirkHoffmann/indico,ThiefMaster/indico,DirkHoffmann/indico,OmeGak/indico,mic4ael/indico,indico/indico,DirkHoffmann/indico,ThiefMaster/indico,OmeGak/indico,DirkHoffmann/indico,indico/indico,OmeGak/indico,mvidalgarcia/indico,indico/indico,pferreir/indico,ThiefMaster/indico,mic4ael/indico,pferreir/indico,pferreir/indico,pferreir/indico,mvidalgarcia/indico,mic4ael/indico,mvidalgarcia/indico,mvidalgarcia/indico,mic4ael/indico