fix for #1191 (extension of Viewer.open() function with initialPage argument)
fix for #1191 (extension of Viewer.open() function with initialPage argument)

seanich/openseadragon,seanich/openseadragon,LarissaSmith/openseadragon,openseadragon/openseadragon,openseadragon/openseadragon,LarissaSmith/openseadragon