OSX-654 Fixes playlist validation for older layouts xibosignage/xibo#1842
OSX-654 Fixes playlist validation for older layouts xibosignage/xibo#1842

alexharrington/xibo-cms,alexharrington/xibo-cms,dasgarner/xibo-cms,alexharrington/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,alexharrington/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,alexharrington/xibo-cms,xibosignage/xibo-cms,dasgarner/xibo-cms,xibosignage/xibo-cms,xibosignage/xibo-cms