fix test imports

These modules were previously visible through the testutils import.
diff --git a/tests/bsn_ipmask.py b/tests/bsn_ipmask.py
index fea7caa..8304958 100644
--- a/tests/bsn_ipmask.py
+++ b/tests/bsn_ipmask.py
@@ -1,8 +1,8 @@
 """
 """
 import struct
-
 import logging
+import scapy
 
 from oftest import config
 import oftest.controller as controller
diff --git a/tests/flow_query.py b/tests/flow_query.py
index 403d138..271be11 100644
--- a/tests/flow_query.py
+++ b/tests/flow_query.py
@@ -63,6 +63,7 @@
 import unittest
 import random
 import time
+import copy
 
 from oftest import config
 import oftest.controller  as controller
diff --git a/tests/pktact.py b/tests/pktact.py
index 7d30698..905780e 100644
--- a/tests/pktact.py
+++ b/tests/pktact.py
@@ -17,6 +17,7 @@
 import time
 import unittest
 import random
+import scapy.all as scapy
 
 from oftest import config
 import oftest.controller as controller