Git commits in Moodle 3.7.0 by David Matamoros

commit baf5551cac4dd9d341a3e622a6c59eb23c28af6c
Author: David Matamoros <davidmc@moodle.com>
Date:   Wed, 24 Apr 2019 23:30:02 +0800
Tag:    v3.7.0-beta

MDL-65412 core_customfield: check configdata link exists

commit 0446fee7a9c99b5cb4f998d2e580906ac020ecc1
Author: David Matamoros <davidmc@moodle.com>
Date:   Fri, 11 Jan 2019 19:12:18 +0800
Tag:    v3.7.0-beta

MDL-57898 core_customfield: Custom fields API

commit 7a0162f17aa3d953cfde87d9d927b0c1fb8ca7e7
Author: David Matamoros <davidmc@moodle.com>
Date:   Fri, 11 Jan 2019 17:56:14 +0800
Tag:    v3.7.0-beta

MDL-57898 core_course: add custom fields support to courses