add a global config dictionary

There was no need for each test module to keep a copy for itself. This means we
can also get rid of test_set_init.
diff --git a/tests/cxn.py b/tests/cxn.py
index 7127a91..eeea564 100644
--- a/tests/cxn.py
+++ b/tests/cxn.py
@@ -10,6 +10,7 @@
 import unittest
 import random
 
+from oftest import config
 import oftest.controller as controller
 import oftest.cstruct as ofp
 import oftest.message as message
@@ -18,25 +19,6 @@
 
 from oftest.testutils import *
 
-#@var cxn_port_map Local copy of the configuration map from OF port
-# numbers to OS interfaces
-cxn_port_map = None
-#@var cxn_config Local copy of global configuration data
-cxn_config = None
-
-def test_set_init(config):
-    """
-    Set up function for connection test classes
-
-    @param config The configuration dictionary; see oft
-    """
-
-    global cxn_port_map
-    global cxn_config
-
-    cxn_port_map = config["port_map"]
-    cxn_config = config
-
 class BaseHandshake(unittest.TestCase):
     """
     Base handshake case to set up controller, but do not send hello.
@@ -62,10 +44,9 @@
                         "Controller startup failed, no switch addr")
 
     def setUp(self):
-        self.config = cxn_config
         logging.info("** START TEST CASE " + str(self))
 
-        self.test_timeout = test_param_get(cxn_config,
+        self.test_timeout = test_param_get(config,
                                            'handshake_timeout') or 60
 
     def inheritSetup(self, parent):
@@ -83,7 +64,6 @@
         the state after the sub_test is run must be taken into account
         by subsequent operations.
         """
-        self.config = parent.config
         logging.info("** Setup " + str(self) + 
                                     " inheriting from " + str(parent))
         self.controller = parent.controller
@@ -109,8 +89,8 @@
     and wait for disconnect.
     """
     def runTest(self):
-        self.controllerSetup(cxn_config["controller_host"],
-                             cxn_config["controller_port"])
+        self.controllerSetup(config["controller_host"],
+                             config["controller_port"])
 
         logging.info("TCP Connected " + 
                         str(self.controller.switch_addr))
@@ -130,8 +110,8 @@
     and wait for disconnect.
     """
     def runTest(self):
-        self.controllerSetup(cxn_config["controller_host"],
-                             cxn_config["controller_port"])
+        self.controllerSetup(config["controller_host"],
+                             config["controller_port"])
 
         logging.info("TCP Connected " + 
                                     str(self.controller.switch_addr))
@@ -157,8 +137,8 @@
     priority = -1
 
     def runTest(self):
-        self.controllerSetup(cxn_config["controller_host"],
-                             cxn_config["controller_port"])
+        self.controllerSetup(config["controller_host"],
+                             config["controller_port"])
 
         logging.info("TCP Connected " + 
                                     str(self.controller.switch_addr))