igmp-test:
   Using json based update of values for igmp groups.

Change-Id: I43e5527580cbd45b0e2509298c2b226c5b126977
diff --git a/src/test/igmp/igmpTest.py b/src/test/igmp/igmpTest.py
index 19e10dc..84fbbac 100644
--- a/src/test/igmp/igmpTest.py
+++ b/src/test/igmp/igmpTest.py
@@ -334,7 +334,7 @@
 
     @deferred(timeout=MCAST_TRAFFIC_TIMEOUT+10)
     def test_igmp_join_verify_traffic(self):
-        groups = ['224.0.1.1', '225.0.0.1']
+        groups = [self.MGROUP1, self.MGROUP1]
 	self.onos_ssm_table_load(groups)
         df = defer.Deferred()
         igmpState = IGMPTestState(groups = groups, df = df)
@@ -364,7 +364,7 @@
 
     @deferred(timeout=MCAST_TRAFFIC_TIMEOUT+40)
     def test_igmp_leave_verify_traffic(self):
-        groups = ['224.0.1.10', '225.0.0.10']
+        groups = [self.MGROUP1, self.MGROUP1]
         leave_groups = ['224.0.1.10']
 	self.onos_ssm_table_load(groups)
         df = defer.Deferred()
@@ -511,7 +511,7 @@
 
     @deferred(timeout=IGMP_QUERY_TIMEOUT + 10)
     def test_igmp_2group_join_latency(self):
-        groups = ['239.0.1.1', '240.0.1.1']
+        groups = [self.MGROUP1, self.MGROUP1]
         df = defer.Deferred()
         def igmp_2group_join_latency():
             self.group_latency_check(groups)