use django-filer for private files
currently we use the rather light-weight django-private-storage package. And we are using django-filer as it's used by django-cms. We should remove the first one as everything can be handled with django-filer
currently we use the rather light-weight django-private-storage package. And we are using django-filer as it's used by django-cms. We should remove the first one as everything can be handled with django-filer