Fix tests in Django 1.7

Django 1.7 doesn't include session or auth middleware
in minimal default config. Djrill admin views require auth.

runtests.py

@@ -21,6 +21,12 @@ settings.configure(
         'django.contrib.sessions',
         'django.contrib.admin',
         APP,
+    ),
+    MIDDLEWARE_CLASSES=(
+        'django.middleware.common.CommonMiddleware',
+        'django.contrib.sessions.middleware.SessionMiddleware',
+        'django.middleware.csrf.CsrfViewMiddleware',
+        'django.contrib.auth.middleware.AuthenticationMiddleware',
     )
 )