Integrate django-scopes (#1319)

* Install django-scopes

* Fix tests.api

* Update tasks and cronjobs

* Fix remaining tests

* Remove unused import

* Fix tests after rebase

* Disable scopes for get_Events_with_any_permission

* Disable scopes for a management command

src/pretix/base/models/devices.py

@@ -4,6 +4,7 @@ from django.db import models
 from django.db.models import Max
 from django.utils.crypto import get_random_string
 from django.utils.translation import ugettext_lazy as _
+from django_scopes import ScopedManager
 
 from pretix.base.models import LoggedModel
 
@@ -71,6 +72,8 @@ class Device(LoggedModel):
         null=True, blank=True
     )
 
+    objects = ScopedManager(organizer='organizer')
+
     class Meta:
         unique_together = (('organizer', 'device_id'),)