[FIX] Fix classic datepicker z-index
[FIX] Fix classic datepicker z-index

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