SeAT Manager (#704)

* SeAT service in modular service app format

* Replace string concatenation with formatters

* Fix incorrect references to user

* Fix exception when user doesn't have seat active

* Prevent deletion of seat API keys by default

* Improve api response error handling

* Corrected notification message

* Added missing view returns

* Update SeAT to use permissions based access

* Update password generator to new style

* Correct logging message

* Fix seat role update tasks

* Correct validate user logic

* Add seat test settings

* Added basic seat unit tests

* Added add permissions function from other branch

* Remove obsolete settings references

services/modules/seat/models.py

@@ -0,0 +1,21 @@
+from __future__ import unicode_literals
+from django.utils.encoding import python_2_unicode_compatible
+from django.contrib.auth.models import User
+from django.db import models
+
+
+@python_2_unicode_compatible
+class SeatUser(models.Model):
+    user = models.OneToOneField(User,
+                                primary_key=True,
+                                on_delete=models.CASCADE,
+                                related_name='seat')
+    username = models.CharField(max_length=254)
+
+    def __str__(self):
+        return self.username
+
+    class Meta:
+        permissions = (
+            ("access_seat", u"Can access the SeAT service"),
+        )