Fixed imageLoaderLimit
Fixed imageLoaderLimit

Currently jobsInProgress was not incremented after adding a job. So it
has gone into the - range and was like unlimited jobs.

ricochet2200/openseadragon,ricochet2200/openseadragon,goofwear/openseadragon,msalsbery/openseadragon,jmnetus/openseadragon,rdlester/openseadragon,lidasong2014/openseadragon,goofwear/openseadragon,shaunstanislaus/openseadragon,seanich/openseadragon,shaunstanislaus/openseadragon,LarissaSmith/openseadragon,mcanthony/openseadragon,avandecreme/openseadragon,LarissaSmith/openseadragon,TMUND/openseadragon,msalsbery/openseadragon,jmnetus/openseadragon,Iced-Tea/openseadragon,Iced-Tea/openseadragon,seanich/openseadragon,mcanthony/openseadragon,TMUND/openseadragon,avandecreme/openseadragon,openseadragon/openseadragon,daverome/openseadragon,rdlester/openseadragon,daverome/openseadragon,lidasong2014/openseadragon,openseadragon/openseadragon