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/etc/tempest.conf.sample b/etc/tempest.conf.sample
index 8d96858..e8f898d 100644
--- a/etc/tempest.conf.sample
+++ b/etc/tempest.conf.sample
@@ -409,3 +409,7 @@
 log_check_interval = 60
 # The default number of threads created while stress test
 default_thread_number_per_action=4
+
+[debug]
+# Enable diagnostic commands
+enable = True