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/flow_expire.py b/tests/flow_expire.py
index 1d05b6b..ab5b68a 100644
--- a/tests/flow_expire.py
+++ b/tests/flow_expire.py
@@ -68,7 +68,7 @@
         self.assertEqual(rc, 0, "Failed to delete all flows")
 
         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")