Navigator now updates properly when reopening a viewer
Navigator now updates properly when reopening a viewer

Before, if you closed a viewer and then opened a new tilesource into
it, the navigator would still have the old tilesource. This patch fixes
that.

goofwear/openseadragon,lidasong2014/openseadragon,goofwear/openseadragon,jmnetus/openseadragon,shaunstanislaus/openseadragon,LarissaSmith/openseadragon,LafayetteCollegeLibraries/openseadragon,mcanthony/openseadragon,janelia-flyem/openseadragon,openseadragon/openseadragon,ricochet2200/openseadragon,LarissaSmith/openseadragon,seanich/openseadragon,msalsbery/openseadragon,janelia-flyem/openseadragon,ricochet2200/openseadragon,daverome/openseadragon,TMUND/openseadragon,Iced-Tea/openseadragon,sul-dlss/openseadragon,avandecreme/openseadragon,Iced-Tea/openseadragon,shaunstanislaus/openseadragon,avandecreme/openseadragon,msalsbery/openseadragon,seanich/openseadragon,openseadragon/openseadragon,rdlester/openseadragon,daverome/openseadragon,jmnetus/openseadragon,rdlester/openseadragon,lidasong2014/openseadragon,TMUND/openseadragon,mcanthony/openseadragon