added utility function to build a URL based on the current window.location (or any arbitrary URL) using active query parameters which can be overridden by function parameter (this was defined in the viewer app)
added utility function to build a URL based on the current window.location
(or any arbitrary URL) using active query parameters which can be
overridden by function parameter (this was defined in the viewer app)

NYPL/readium-shared-js,kivuto/readium-shared-js,JoMedia/readium-shared-js,NYPL-Simplified/readium-shared-js,ravn-no/readium-shared-js,NYPL-Simplified/readium-shared-js,kivuto/readium-shared-js,NYPL/readium-shared-js,ravn-no/readium-shared-js,readium/readium-shared-js,readium/readium-shared-js