Git commits in Moodle 3.4.0 by Craig R Morton

commit 6961f78dcae1c0e217e6e0817813570f15af3d54
Author: Craig R Morton <craig@moodle.com>
Date:   Fri, 06 Jan 2017 13:48:07 +0800
Tag:    v3.4.0-beta

MDL-60309 theme_boost: Add background image filepicker to Boost