Add OpenAPI annotations for rrules and settings

Added some missing OpenAPI annotations for rrule and settings. Not sure if that's intended or the right way - please check.

(and it reverts commit 789cf19c which was just used for testing the merge policies)

program/tests/test_hosts.py

@@ -74,7 +74,7 @@ def test_update_host(admin_api_client, host, image):
 
     response = admin_api_client.put(url(host), data=update)
 
-    assert response.status_code == 201
+    assert response.status_code == 200
 
     assert_data(response, update)