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/groupmanagement/context_processors.py

@@ -0,0 +1,5 @@
+from allianceauth.groupmanagement.managers import GroupManager
+
+
+def can_manage_groups(request):
+    return {'can_manage_groups': GroupManager.can_manage_groups(request.user)}