Test: Add cbench test case for igmp join leave loop test.
cbench code was modified as in cbench.patch to add igmp packet in support.
Disable vtn app activation as it is buggy and fails activation.

Change-Id: Ia37ad3d9e6011b970e24bcb9e0a2bb783e334545
diff --git a/src/test/setup/cord-test.py b/src/test/setup/cord-test.py
index df0e26d..529103c 100755
--- a/src/test/setup/cord-test.py
+++ b/src/test/setup/cord-test.py
@@ -410,7 +410,7 @@
             Onos.install_cord_apps(onos_ip = onos_ip)
         except: pass
 
-    print('Installing cord tester ONOS app %s' %onos_app_file)
+    print('Installing cord tester ONOS app %s' %args.app)
     try:
         OnosCtrl.install_app(args.app, onos_ip = onos_ip)
     except: pass
@@ -620,7 +620,7 @@
             Onos.install_cord_apps(onos_ip = onos_ip)
         except: pass
 
-    print('Installing cord tester ONOS app %s' %onos_app_file)
+    print('Installing cord tester ONOS app %s' %args.app)
     try:
         for ip in onos_ips:
             OnosCtrl.install_app(args.app, onos_ip = ip)