Fix category-less event creation page
Fix category-less event creation page

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