Git merges in Moodle 3.1.9 by Damyon Wiese

commit 2393486db4c74ed631d5dec8770eb312398d8a96
Author: Damyon Wiese <damyon@moodle.com>
Date:   Thu, 26 Oct 2017 16:05:16 +0800
Tag:    v3.1.9

Merge branch 'MDL-60366_feedback_upgrade_31' of git://github.com/davosmith/moodle into MOODLE_31_STABLE