Convert MEDIA_ROOT to unicode to avoid UnicodeWarning
Convert MEDIA_ROOT to unicode to avoid UnicodeWarning

jwinzer/OpenSlides,CatoTH/OpenSlides,FinnStutzenstein/OpenSlides,normanjaeckel/OpenSlides,emanuelschuetze/OpenSlides,CatoTH/OpenSlides,boehlke/OpenSlides,FinnStutzenstein/OpenSlides,OpenSlides/OpenSlides,jwinzer/OpenSlides,ostcar/OpenSlides,boehlke/OpenSlides,rolandgeider/OpenSlides,ostcar/OpenSlides,ostcar/OpenSlides,tsiegleauq/OpenSlides,FinnStutzenstein/OpenSlides,rolandgeider/OpenSlides,FinnStutzenstein/OpenSlides,normanjaeckel/OpenSlides,emanuelschuetze/OpenSlides,jwinzer/OpenSlides,tsiegleauq/OpenSlides,normanjaeckel/OpenSlides,CatoTH/OpenSlides,CatoTH/OpenSlides,jwinzer/OpenSlides,emanuelschuetze/OpenSlides,boehlke/OpenSlides,OpenSlides/OpenSlides,emanuelschuetze/OpenSlides,jwinzer/OpenSlides,boehlke/OpenSlides,tsiegleauq/OpenSlides,rolandgeider/OpenSlides,normanjaeckel/OpenSlides