Merge pull request #1281 from mboersma/update-django-guardian

chore(requirements): update django-guardian to v1.4.8

Author: mboersma

rootfs/requirements.txt

@@ -3,7 +3,7 @@ backoff==1.4.0
 Django==1.11
 django-auth-ldap==1.2.10
 django-cors-middleware==1.3.1
-django-guardian==1.4.6
+django-guardian==1.4.8
 djangorestframework==3.6.2
 docker-py==1.10.6
 gunicorn==19.7.1