Git commits in Moodle 3.6.0 by Vadim Tabunshchik

commit d5f47f8f390d3293ac9f448e4110c492238a70b3
Author: Vadim Tabunshchik <tvn.pstu@gmail.com>
Date:   Thu, 19 Jul 2018 16:29:34 +0800
Tag:    v3.6.0-beta

MDL-62871 quiz: incorrect foreign key declaration