Add client authentication to the LB cookbook
Add client authentication to the LB cookbook

This patch adds a cookbook section for creating client authentication
enabled listeners.

It also removes two references to granting access to secrets in
barbican that are no longer required.

Change-Id: Iaada1b5d519bfc57528aa15bae8c0ee2b55f0567

openstack/octavia,openstack/octavia,openstack/octavia