Author: Mathew May
MDL-78100 gradereport_grader: Clear all button to reset filters
http://git.moodle.org/gw?p=moodle.git;a=commit;h=9f5e343d7337241c87b72db8f56678ca84799e37
http://github.com/moodle/moodle/commit/9f5e343d7337241c87b72db8f56678ca84799e37
+ 4.3 en [clearall,gradereport_grader]
+ 4.3 en [clearsearch,gradereport_grader]