Dump basic network info  in the test_network_basic_ops

Add minimal debug debug capability for basic network informations,
These information, especially the nat rules in the router namespaces
 usually very helpful.

Change-Id: I8840cb5e388fc8b674b66f8de4e25754ccbe0863
diff --git a/tempest/config.py b/tempest/config.py
index 7245b10..ce87bc6 100644
--- a/tempest/config.py
+++ b/tempest/config.py
@@ -609,6 +609,21 @@
     for opt in ServiceAvailableGroup:
         conf.register_opt(opt, group='service_available')
 
+debug_group = cfg.OptGroup(name="debug",
+                           title="Debug System")
+
+DebugGroup = [
+    cfg.BoolOpt('enable',
+                default=True,
+                help="Enable diagnostic commands"),
+]
+
+
+def register_debug_opts(conf):
+    conf.register_group(debug_group)
+    for opt in DebugGroup:
+        conf.register_opt(opt, group='debug')
+
 
 @singleton
 class TempestConfig: