Return org_type in list of all organisations

This will let us do some filtering of this list in the admin. It’s
better to do it there because it means the admin can use the same cached
response from Redis each time.

app/models.py

@@ -427,6 +427,7 @@ class Organisation(db.Model):
             'active': self.active,
             'count_of_live_services': len(self.live_services),
             'domains': self.domain_list,
+            'organisation_type': self.organisation_type,
         }