Author: Andrew Nicols
MDL-53566 core: Allow admins more control over locking
This change allows sites to configure locking such that it does not
apply to administrators at all.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=bb41db9ce0dbf980f65db9f1899fc1e3b91964ee
http://github.com/moodle/moodle/commit/bb41db9ce0dbf980f65db9f1899fc1e3b91964ee
+ 3.6 en [contextlockappliestoadmin,core_admin]
+ 3.6 en [contextlockappliestoadmin_desc,core_admin]