This change adds the keystonemiddleware audit paste filter[0]
and enables it for the cinder-api and cinder-scheduler services.
This provides the ability to audit API requests for cinder.
[0] https://docs.openstack.org/keystonemiddleware/latest/audit.html
Change-Id: If81b88a4003bc4394ef4a378626cf5d6edb9c4ae