Make keystone verify configurable

In some cases, such as test environements, it is required
to run with an insecure keystone connection. Allow for a
configuration option to set the verify flag.

Change-Id: I4b0658322b5d737b116d5659551fb2fe4f9e68a1

etc/octavia.conf

@@ -51,6 +51,7 @@
 # admin_user = octavia
 # admin_password = password
 # admin_tenant_name = service
+# insecure = False
 
 [keystone_authtoken_v3]
 # If using Keystone v3

octavia/common/keystone.py

@@ -60,7 +60,8 @@ def get_session():
 
         try:
             kc = client.Password(**kwargs)
-            _SESSION = session.Session(auth=kc)
+            _SESSION = session.Session(
+                auth=kc, verify=not cfg.CONF.keystone_authtoken.insecure)
         except Exception:
             with excutils.save_and_reraise_exception():
                 LOG.exception(_LE("Error creating Keystone session."))