Implement a required_wildcards setting to allow testing switches that
don't support certain match fields; implement l3-l4 for forcing
wildcarding of all L3 and L4 fields; clean up flow_query test a bit
diff --git a/tests/port_stats.py b/tests/port_stats.py
index 087e725..0964774 100644
--- a/tests/port_stats.py
+++ b/tests/port_stats.py
@@ -165,7 +165,7 @@
 
         # build packet
         pkt = simple_tcp_packet()
-        match = parse.packet_to_flow_match(pkt)
+        match = packet_to_flow_match(self, pkt)
         match.wildcards &= ~ofp.OFPFW_IN_PORT
         self.assertTrue(match is not None, 
                         "Could not generate flow match from pkt")
@@ -218,7 +218,7 @@
     """
 
     def buildFlowModMsg(self, pkt, ingress_port, egress_port):
-        match = parse.packet_to_flow_match(pkt)
+        match = packet_to_flow_match(self, pkt)
         match.wildcards &= ~ofp.OFPFW_IN_PORT
         self.assertTrue(match is not None, 
                         "Could not generate flow match from pkt")