Fix GTFS.xml (#25)

Changes:
- GTFS fix: `service_id` and `route_id` columns were selected in the
wrong order

docs/GTFS.xml

@@ -446,7 +446,7 @@ FROM trips_input
 GROUP BY trip_id, service_id, route_id, date;
 
 INSERT INTO trips_mdb(trip_id, service_id, route_id, date, trip)
-SELECT trip_id, route_id, t.service_id, d.date,
+SELECT trip_id, t.service_id, route_id, d.date,
   shift(trip, make_interval(days => d.date - t.date))
 FROM trips_mdb t JOIN service_dates d ON t.service_id = d.service_id AND t.date <> d.date;
 			</programlisting>