Git commits in Moodle 3.6.5 by Dan Marsden

commit b48c1715dfd6b776a495f43ff1fc5858981a2d01
Author: Dan Marsden <dan@danmarsden.com>
Date:   Fri, 14 Jun 2019 10:02:13 +0800
Tag:    v3.6.5

MDL-60347 core: debugsmtp should be a developer only setting.