Updated openstack/openstack
Project: openstack/oslo.messaging  22c8bfddee903bdf0bb25c39dfcf4d470221f6b5

Add missing docs for list_opts()

Seems I forgot to check this in as part of commit 0eb5a6f.

Change-Id: I4e3128f726873998fb9c1cde78864e06e225e5bd