ADD: dav_base: some simple test cases.

dav_base/tests/test_apps.py

@@ -0,0 +1,16 @@
+from django.apps import apps
+from django.test import TestCase
+
+
+class AppsTestCase(TestCase):
+    def setUp(self):
+        app_config = apps.get_containing_app_config(__package__)
+        self.settings = app_config.settings
+
+    def test_settings(self):
+        setting_names = ('email_sender',
+                         'email_base_url',
+                         'email_subject_prefix')
+
+        for s in setting_names:
+            self.assertTrue(hasattr(self.settings, s), 'Settings do not contain {}'.format(s))