Add an optional tenant flow log offload test

This patch adds an optional tenant flow log offload scenario test
that checks the tenant flow logging offload and format.

Change-Id: I8a7ed4e1bc3d567c4807726c684ad86cd281096f
diff --git a/octavia_tempest_plugin/config.py b/octavia_tempest_plugin/config.py
index 8573d89..2560631 100644
--- a/octavia_tempest_plugin/config.py
+++ b/octavia_tempest_plugin/config.py
@@ -198,6 +198,11 @@
     cfg.BoolOpt('test_reuse_connection', default=True,
                 help='Reuse TCP connections while testing LB with '
                      'HTTP members (keep-alive).'),
+    # Log offloading specific options
+    cfg.StrOpt('tenant_flow_log_file',
+               default='/var/log/octavia-tenant-traffic.log',
+               help='File path, on the tempest system, to the tenant flow '
+                    'log file.'),
 ]
 
 lb_feature_enabled_group = cfg.OptGroup(name='loadbalancer-feature-enabled',
@@ -231,4 +236,8 @@
                 default=True,
                 help="Whether session persistence is supported with the "
                      "provider driver."),
+    cfg.BoolOpt('log_offload_enabled', default=False,
+                help="Whether the log offload tests will run. These require "
+                     "the tempest instance have access to the log files "
+                     "specified in the tempest configuration."),
 ]