This patch fixes the problems found in the api-ref doc for stack
resources. More specifically, changes include:
- Add 'physical_resource_id' as a query parameter;
- Add 'resource_id' as a query parameter;
- Add 'with_attr' parameter when showing resource;
- Add API doc for resource-mark-unhealthy;
- Add response parameters for resource-show-metadata API;
- Add missing fields such 'links', openstack-request-id in some responses.
- Add a special description for the 400 status code of resource-signal.
Change-Id: I6e6889e79f25431278e82b2c499267d8853470d1