Git commits in Moodle 3.4.1 by Marcus Boon

commit 7da0e04ca349082a4205b8a87a9eaf1cdd7f00a5
Author: Marcus Boon <marcus@catalyst-au.net>
Date:   Thu, 13 Jul 2017 12:44:29 +0800
Tag:    v3.4.1

MDL-59866 session: Add retry for redis sessions