Enable hacking extensions framework

<long rant deleted>

This change enables the hacking extensions ability in trove. That
includes bumping the version of hacking that we use, and also adding
the enable-extensions like in the [flake8] section. I've enabled two
of the hacking extensions here.

There are some limitations to the hacking rules that I've enabled so
I'm also going to enter two bugs that others can fix (if they so
desire).

Change-Id: I6d8fc4bc03f948b84ad823e5248d78a4caa5c042
Related-Bug: 1642554
Related-Bug: 1642552

test-requirements.txt

@@ -2,7 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 # Hacking already pins down pep8, pyflakes and flake8
-hacking<0.11,>=0.10.0
+hacking<0.13,>=0.12.0 # Apache-2.0
 bandit>=1.1.0 # Apache-2.0
 sphinx!=1.3b1,<1.4,>=1.2.1 # BSD
 os-api-ref>=1.0.0 # Apache-2.0

tox.ini

@@ -72,6 +72,7 @@ show-source = True
 # H301 is ignored on purpose.
 # The rest of the ignores are TODOs.
 ignore = F821,H301,H404,H405,H501
+enable-extensions = H203,H106
 builtins = _
 exclude=.venv,.tox,.git,dist,doc,*egg,tools,etc,build,*.po,*.pot,integration
 filename=*.py,trove-*

trove/tests/unittests/common/test_dbmodels.py

@@ -135,7 +135,7 @@ class DatastoreUserTest(trove_testtools.TestCase):
 
     def _test_user_basic(self, user):
         self.assertEqual(self.username, user.name)
-        self.assertEqual(None, user.password)
+        self.assertIsNone(user.password)
         self.assertEqual(self.host_wildcard, user.host)
         self.assertEqual([], user.databases)
 
@@ -316,7 +316,7 @@ class DatastoreUserTest(trove_testtools.TestCase):
     def test_validate_dict_defaults(self):
         user = models.DatastoreUser(self.username)
         user.verify_dict()
-        self.assertEqual(None, user.password)
+        self.assertIsNone(user.password)
         self.assertEqual(self.host_wildcard, user.host)
         self.assertEqual([], user.databases)
 

trove/tests/unittests/secgroups/test_security_group.py

@@ -164,8 +164,8 @@ class SecurityGroupDeleteTest(trove_testtools.TestCase):
         sec_mod.SecurityGroupInstanceAssociation.find_by = Mock(
             return_value=fake_SecGr_Association())
         sec_mod.SecurityGroupInstanceAssociation.delete = self.fException
-        self.assertNotEqual(sec_mod.SecurityGroupInstanceAssociation.find_by(
-            i_id, deleted=False).get_security_group(), None)
+        self.assertIsNotNone(sec_mod.SecurityGroupInstanceAssociation.find_by(
+            i_id, deleted=False).get_security_group())
         self.assertTrue(hasattr(sec_mod.SecurityGroupInstanceAssociation.
                                 find_by(i_id, deleted=False).
                                 get_security_group(), 'delete'))