TL;DR: safer deployment and minor fixes

- Instead of modifying cdb_service_quota_info to return max_batch_size,
a new type (service_quota_info_batch) and a new function
(cdb_service_quota_info_batch) are created. That makes deployment safe.
- Fixes geocoding with forced batch size 1.
- Improves namespacing for count_estimate (->
cdb_dataservices_client.cdb_count_estimate).
- Improves namespacing for jsonb_array_casttext (->
cdb_dataservices_client.cdb_jsonb_array_casttext).

server/extension/sql/21_bulk_geocode_street.sql

@@ -35,8 +35,7 @@ RETURNS SETOF cdb_dataservices_server.geocoding AS $$
       raise Exception('Requested geocoder is not available')
 
     plan = plpy.prepare("SELECT * FROM cdb_dataservices_server.{}($1, $2, $3); ".format(provider_function), ["text", "text", "jsonb"])
-    result = plpy.execute(plan, [username, orgname, searches])
-    return result
+    return plpy.execute(plan, [username, orgname, searches])
 
 $$ LANGUAGE plpythonu STABLE PARALLEL RESTRICTED;