Git merges in Moodle 3.1.8 by Dan Poltawski

commit f3fe4f52e12497c84cf5e99e9a130cbef5d58837
Author: Dan Poltawski <dan@moodle.com>
Date:   Thu, 20 Jul 2017 20:21:00 +0800
Tag:    v3.1.8

Merge branch 'install_31_STABLE' of https://git.in.moodle.com/amosbot/moodle-install into MOODLE_31_STABLE

commit f06abbd040140c88e8eae9c90ca94cc67cf453ef
Author: Dan Poltawski <dan@moodle.com>
Date:   Wed, 19 Jul 2017 16:33:31 +0800
Tag:    v3.1.8

Merge branch 'wip-MDL-57649-31-fix' of git://github.com/abgreeve/moodle into MOODLE_31_STABLE

commit 5db085f0a74149cc0a00d77cf8720df2124d89e2
Author: Dan Poltawski <dan@moodle.com>
Date:   Mon, 17 Jul 2017 16:01:12 +0800
Tag:    v3.1.8

Merge branch 'wip-MDL-57649-31' of git://github.com/abgreeve/moodle into MOODLE_31_STABLE

commit 4fc794b7efb04b69fa6dadb35b345abaf31e1821
Author: Dan Poltawski <dan@moodle.com>
Date:   Fri, 14 Jul 2017 18:46:54 +0800
Tag:    v3.1.8

Merge branch 'install_31_STABLE' of https://git.in.moodle.com/amosbot/moodle-install into MOODLE_31_STABLE