Upstream OpenSeadragon patch

[tokee]

Using OpenSeadragon 2.1.1 with the DeepZoom-protocol against IIPImage server that nrtmosaic emulates does not work when tileSources is specified using DZI. This is related to openseadragon/openseadragon#411 and openseadragon/openseadragon#413

A hackish fix is to edit openseadragon.js by replacing the lines

            options.tilesUrl = url.replace(
                    /([^\/]+?)(\.(dzi|xml|js))?\/?(\?.*)?$/, '$1_files/');

with

            options.tilesUrl = url.replace(
                    /([^\/]+)\.(dzi|xml|js)(\?.*|$)/, '$1_files/');

Unfortunately the implications are not clear at this point. This should be investigated and hopefully upstreamed to OpenSeadragon.