code: def add_to_manifest(self, manifest):
          
          # Add this service to list of services
          manifest.add_service(self.service.name)
  
          # Add environment variables
          manifest.add_env_var(self.__module__ + '.uri',
                  self.service.settings.data['url'])
          manifest.add_env_var(self.__module__ + '.zone_id',
                  self.get_predix_zone_id())
  
          manifest.write_manifest()
docs: Add useful details to the manifest about this service
          so that it can be used in an application.
  
          :param manifest: An predix.admin.app.Manifest object
              instance that manages reading/writing manifest config
              for a cloud foundry app.