Add Event.get_contribution()
Add Event.get_contribution()

Makes sense to have it along get_session()

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