Git commits in Moodle 3.8.0 by Mark Johnson

commit 3b75d14315a4576cfb7c4bcfee0fd06ffbc588df
Author: Mark Johnson <mark.johnson@open.ac.uk>
Date:   Thu, 08 Aug 2019 16:08:08 +0800
Tag:    v3.8.0-beta

MDL-66336 courses: Show an error when no course categories are visible

commit 288d6ebb5492ebbe651ff46b84ca0682f5ab99bf
Author: Mark Johnson <mark@barrenfrozenwasteland.com>
Date:   Wed, 17 Apr 2019 01:31:51 +0800
Tag:    v3.8.0-beta

MDL-65369 events: Include changed course settings in course_updated

commit f3c9599e1fbf3e730c229ce93909000d5e6304cd
Author: Mark Johnson <mark.johnson@open.ac.uk>
Date:   Thu, 11 Apr 2019 16:02:31 +0800
Tag:    v3.8.0-beta

MDL-65335 auth: Make oauth2 enabled check more efficient

commit d91aa1e76030751a7c9fac27cc34f449179e32cf
Author: Mark Johnson <mark.johnson@open.ac.uk>
Date:   Wed, 10 Apr 2019 23:27:36 +0800
Tag:    v3.8.0-beta

MDL-65327 performance: Lazy-load module name strings