python3: unittest define main

Code change to unit tests for python3.

partial: https://github.com/vmware/pyvmomi/issues/55

test-requirements.txt

@@ -1,5 +1,4 @@
 contextdecorator
-mock
 PyYAML>=3.11
 testtools>=0.9.34
 vcrpy

tests/test_connect.py

@@ -62,3 +62,6 @@ class ConnectionTests(unittest.TestCase):
         # NOTE (hartsock): assertIsNotNone does not work in Python 2.6
         self.assertTrue(session_id is not None)
         self.assertEqual('52773cd3-35c6-b40a-17f1-fe664a9f08f3', session_id)
+
+if __name__ == '__main__':
+    unittest.main()