refactor verify_flowstats and move to testutils

This needs to be centralized for later byte counter fuzzing changes.
diff --git a/tests/counters.py b/tests/counters.py
index 4caae4f..d23cf75 100644
--- a/tests/counters.py
+++ b/tests/counters.py
@@ -60,9 +60,9 @@
         num_pkts = 5 
         for pkt_cnt in range(num_pkts):
             self.dataplane.send(of_ports[0],str(pkt))
-         
-        #Verify Recieved Packets/Bytes Per Flow  
-        verify_flowstats(self,match,packet_count=num_pkts)
+
+        # Verify the packet counter was updated
+        verify_flow_stats(self, match, pkts=num_pkts)
 
 
 class BytPerFlow(base_tests.SimpleDataPlane):
@@ -93,9 +93,9 @@
         byte_count = num_pkts*len(str(pkt))
         for pkt_cnt in range(num_pkts):
             self.dataplane.send(of_ports[0],str(pkt))
-         
-        #Verify Recieved Packets/Bytes Per Flow  
-        verify_flowstats(self,match,byte_count=byte_count)
+
+        # Verify the byte counter was updated
+        verify_flow_stats(self, match, bytes=byte_count)
 
 
 class DurationPerFlow(base_tests.SimpleDataPlane):