Git commits in Moodle 3.4.0 by Marco Ferrante

commit a86dbfbb3dd01d8302c7f29a46001ae901e7491b
Author: Marco Ferrante <marco@csita.unige.it>
Date:   Thu, 13 Jul 2017 16:08:52 +0800
Tag:    v3.4.0-beta

MDL-59432 auth_db: add aliases to field mapping query