code: function(display) {
        if(display) {
           Dom.addClass(this.el, this.dropinviteClassName);
        }
        else {
           Dom.removeClass(this.el, this.dropinviteClassName);
        }
     }
docs: Show or hide the drop invitation. (by adding/removing this.options.dropinviteClassName CSS class)
  @method setDropInvitation
  @param {Boolean} display Show the invitation if true, hide it otherwise