Git commits in Moodle 3.2.4 by Eloy Lafuente (stronk7)

commit 8ae8ed4aca751673901e134e537924e3ea204414
Author: Eloy Lafuente (stronk7) <stronk7@moodle.org>
Date:   Tue, 13 Jun 2017 15:59:52 +0800
Tag:    v3.2.4

MDL-46322 database: alias sort fields to avoid ambiguous naming