Author: Jun Pataleta
MDL-80043 gradereport_grader: Define `editingmode_title` lang string
http://git.moodle.org/gw?p=moodle.git;a=commit;h=cc6b3c161f586d505f9afbb3998ff482a8a90c26
http://github.com/moodle/moodle/commit/cc6b3c161f586d505f9afbb3998ff482a8a90c26
+ 4.1 en [editingmode_title,gradereport_grader]