Git commits in Moodle 3.6.2 by Bas Brands

commit ceb92a35535c7574189c6949dbf3945105c182ad
Author: Bas Brands <bas@moodle.com>
Date:   Mon, 17 Dec 2018 22:02:38 +0800
Tag:    v3.6.2

MDL-64419 core_message: fix user info in bootstrapbase message drawer


commit 0cd2c36605c47d0eb216a77bf5fd084c67446523
Author: Bas Brands <bas@moodle.com>
Date:   Fri, 14 Dec 2018 23:28:36 +0800
Tag:    v3.6.2

MDL-64392 core_question: flexbox compatible separator for question types


commit 99440d3db711eec490c38fd58c2b9b22bc98dc87
Author: Bas Brands <bas@moodle.com>
Date:   Thu, 13 Dec 2018 22:00:27 +0800
Tag:    v3.6.2

MDL-64388 core_themes: update docs on new required output method


commit ea6ae74019ca8f67d7d84506c31ac790c744fe51
Author: Bas Brands <bas@moodle.com>
Date:   Wed, 12 Dec 2018 01:45:02 +0800
Tag:    v3.6.2

MDL-64038 core_message: add default group image