Decorate mailqueue views with @login_required

We did explicitly check for superuser permissions, so there was no way
to get in, but without the decorator we wouldn't get the redirect to the
login page.

postgresqleu/mailqueue/backendviews.py

@@ -1,13 +1,15 @@
 from django.core.exceptions import PermissionDenied
 from django.shortcuts import get_object_or_404
 from django.http import Http404, HttpResponse
+from django.contrib.auth.decorators import login_required
 
 from postgresqleu.util.backendviews import backend_list_editor
 from postgresqleu.mailqueue.backendforms import BackendMailqueueForm
 from postgresqleu.mailqueue.models import QueuedMail
 from postgresqleu.mailqueue.util import parse_mail_content, recursive_parse_attachments_from_message
 
 
+@login_required
 def edit_mailqueue(request, rest):
     if not request.user.is_superuser:
         raise PermissionDenied("Access denied")
@@ -24,6 +26,7 @@ def edit_mailqueue(request, rest):
     )
 
 
+@login_required
 def view_attachment(request, queueid, attname):
     if not request.user.is_superuser:
         raise PermissionDenied("Access denied")