Oslo.policy is moving away from using json format policy files.
This patch updates the Octavia documentation, policy configuration file, and
legacy admin-or-owner policy file to be in yaml format.
Octavia will continue to honor and support the json format file as long
as oslo.policy does, but this patch will encourage new deployments
to use the yaml format.
This patch adds policies and enforcement to the Octavia v2 API for
load balancers and listeners. Child patches will add the rest of the API.
In this patch I also correct some improper functional tests.