Git commits in Moodle 3.6.x by Brendan Heywood

commit ddc5472056a627c61ee8cc04b170d69fef16974e
Author: Brendan Heywood <brendan@catalyst-au.net>
Date:   Tue, 05 Nov 2019 07:32:47 +0800
Tag:    v3.6.7

MDL-66984 auth: Allow $USER to be used in change_password_url

commit 1aabe01886a47ce8d4220c1210ba1ac6326274f4
Author: Brendan Heywood <brendan@catalyst-au.net>
Date:   Thu, 17 Oct 2019 08:01:33 +0800
Tag:    v3.6.7

MDL-66935 core_lock: Fix resource key clashes in db and postgres locks

commit 4ad8be5c627f1cb6b7ecd96d1e939e765589a933
Author: Brendan Heywood <brendan@catalyst-au.net>
Date:   Fri, 14 Dec 2018 11:43:02 +0800
Tag:    v3.6.4

MDL-64394 core: Fixed bug when using access log with pre_loginpage_hook