Python 3 Fixes: Replace missing builtins

There are a few different missing builtins in python3 that we're using.
This shows up when running tox pep8 under python3 which is needed for
the streamer work.

Change-Id: I1b2ef0b7bdcd1a85895576682455745fe06e880b
diff --git a/tests/base.py b/tests/base.py
index 3c28a72..e7da178 100755
--- a/tests/base.py
+++ b/tests/base.py
@@ -27,6 +27,7 @@
 import re
 import select
 import shutil
+from six.moves import reload_module
 import socket
 import string
 import subprocess
@@ -916,8 +917,8 @@
         os.environ['STATSD_PORT'] = str(self.statsd.port)
         self.statsd.start()
         # the statsd client object is configured in the statsd module import
-        reload(statsd)
-        reload(zuul.scheduler)
+        reload_module(statsd)
+        reload_module(zuul.scheduler)
 
         self.gearman_server = FakeGearmanServer()