def get(uri)
      uri = Resync::XML.to_uri(uri)
      @helper.fetch(uri: uri)
    end
def get(uri)
      uri = Resync::XML.to_uri(uri)
      @helper.fetch(uri: uri)
    end
Gets the content of the specified URI as a string.
 @param uri [URI, String] the URI to download
 @return [String] the content of the URI