Restructure Alliance Auth package (#867)

* Refactor allianceauth into its own package

* Add setup

* Add missing default_app_config declarations

* Fix timerboard namespacing

* Remove obsolete future imports

* Remove py2 mock support

* Remove six

* Add experimental 3.7 support and multiple Dj versions

* Remove python_2_unicode_compatible

* Add navhelper as local package

* Update requirements

allianceauth/services/modules/example/models.py

@@ -0,0 +1,13 @@
+from django.contrib.auth.models import User
+from django.db import models
+
+
+class ExampleUser(models.Model):
+    user = models.OneToOneField(User,
+                                primary_key=True,
+                                on_delete=models.CASCADE,
+                                related_name='example')
+    username = models.CharField(max_length=254)
+
+    def __str__(self):
+        return self.username