Updated openstack/openstack
Project: openstack/nova  93d5abf29bbdf4ddcd2927d8dc5c4d39672a9b76

Adds API microversion response headers

Adds the following headers to REST API headers for API
microversions:

X-OpenStack-Compute-API-Version: Version
Vary: X-OpenStack-Compute-API-Version

Partially implements blueprint api-microversions

Change-Id: I5748d7b81b355bf8aad6bb8703d1a29a97798452