Always use Pythons builtin unittest module

As we've dropped Python 2.6, the builtin unittest module will always be
unittest2

wagtail/tests/utils.py

@@ -5,17 +5,6 @@ import threading
 from django.contrib.auth import get_user_model
 from django.utils import six
 
-# We need to make sure that we're using the same unittest library that Django uses internally
-# Otherwise, we get issues with the "SkipTest" and "ExpectedFailure" exceptions being recognised as errors
-try:
-    # Firstly, try to import unittest from Django
-    from django.utils import unittest
-except ImportError:
-    # Django doesn't include unittest
-    # We must be running on Django 1.7+ which doesn't support Python 2.6 so
-    # the standard unittest library should be unittest2
-    import unittest
-
 
 class WagtailTestUtils(object):
     def login(self):

wagtail/wagtailadmin/tests/test_pages_views.py

@@ -1,4 +1,5 @@
 from datetime import timedelta
+import unittest
 
 from django.test import TestCase
 from django.core.urlresolvers import reverse
@@ -13,7 +14,7 @@ from wagtail.tests.models import (
     StandardIndex, StandardChild,
     BusinessIndex, BusinessChild, BusinessSubIndex,
     TaggedPage, Advert, AdvertPlacement)
-from wagtail.tests.utils import unittest, WagtailTestUtils
+from wagtail.tests.utils import WagtailTestUtils
 from wagtail.wagtailcore.models import Page, PageRevision
 from wagtail.wagtailcore.signals import page_published, page_unpublished
 from wagtail.wagtailusers.models import UserProfile

wagtail/wagtaildocs/tests.py

@@ -1,4 +1,5 @@
 from six import b
+import unittest
 
 from django.test import TestCase
 from django.contrib.auth import get_user_model
@@ -7,7 +8,7 @@ from django.core.urlresolvers import reverse
 from django.core.files.base import ContentFile
 from django.test.utils import override_settings
 
-from wagtail.tests.utils import unittest, WagtailTestUtils
+from wagtail.tests.utils import WagtailTestUtils
 from wagtail.wagtailcore.models import Page
 
 from wagtail.tests.models import EventPage, EventPageRelatedLink

wagtail/wagtailembeds/tests.py

@@ -3,6 +3,7 @@ from six.moves.urllib.error import URLError
 
 from mock import patch
 import warnings
+import unittest
 
 try:
     import embedly
@@ -13,7 +14,7 @@ except ImportError:
 from django import template
 from django.test import TestCase
 
-from wagtail.tests.utils import WagtailTestUtils, unittest
+from wagtail.tests.utils import WagtailTestUtils
 
 from wagtail.wagtailembeds.embeds import (
     EmbedNotFoundException,

wagtail/wagtailimages/tests/test_models.py

@@ -1,3 +1,5 @@
+import unittest
+
 from django.test import TestCase
 from django.core.urlresolvers import reverse
 from django.test.utils import override_settings
@@ -8,7 +10,7 @@ from django.core.files.uploadedfile import SimpleUploadedFile
 from django.db.utils import IntegrityError
 from django.db import connection
 
-from wagtail.tests.utils import WagtailTestUtils, unittest, test_concurrently
+from wagtail.tests.utils import WagtailTestUtils, test_concurrently
 from wagtail.wagtailcore.models import Page
 from wagtail.tests.models import EventPage, EventPageCarouselItem
 from wagtail.wagtailimages.models import Rendition, Filter

wagtail/wagtailsearch/tests/test_backends.py

@@ -1,12 +1,13 @@
 from six import StringIO
 import warnings
+import unittest
 
 from django.test import TestCase
 from django.test.utils import override_settings
 from django.conf import settings
 from django.core import management
 
-from wagtail.tests.utils import unittest, WagtailTestUtils
+from wagtail.tests.utils import WagtailTestUtils
 from wagtail.tests import models
 from wagtail.wagtailsearch.backends import get_search_backend, InvalidSearchBackendError
 from wagtail.wagtailsearch.backends.db import DBSearch

wagtail/wagtailsearch/tests/test_db_backend.py

@@ -1,4 +1,4 @@
-from wagtail.tests.utils import unittest
+import unittest
 
 from django.test import TestCase
 

wagtail/wagtailsearch/tests/test_elasticsearch_backend.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 from __future__ import unicode_literals
 
-from wagtail.tests.utils import unittest
+import unittest
 import datetime
 import json
 

wagtail/wagtailusers/tests.py

@@ -1,14 +1,17 @@
 from __future__ import unicode_literals
+
+import unittest
+import six
+
 from django.test import TestCase
 from django.core.urlresolvers import reverse
 from django.contrib.auth import get_user_model
 from django.contrib.auth.models import Group, Permission
 
-from wagtail.tests.utils import WagtailTestUtils, unittest
+from wagtail.tests.utils import WagtailTestUtils
 from wagtail.wagtailcore import hooks
 from wagtail.wagtailusers.models import UserProfile
 from wagtail.wagtailcore.models import Page, GroupPagePermission
-import six
 
 
 class TestUserIndexView(TestCase, WagtailTestUtils):