added a button for browser supporting folder uploads. refs #712
added a button for browser supporting folder uploads. refs #712

samvera/hyrax,zhang4952/scholarsphere,samvera/hyrax,jeremyf/sufia,ndlib/scholarsphere,jeremyf/sufia,zhang4952/scholarsphere,ndlib/scholarsphere,zhang4952/scholarsphere,samvera/hyrax,samvera/hyrax,ndlib/scholarsphere,zhang4952/scholarsphere