Author: Rossiani Wijaya
MDL-14238 - add filter to grade assignment.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=fdb797adcf4399cde79f699db04f3749a9ca4638
http://github.com/moodle/moodle/commit/fdb797adcf4399cde79f699db04f3749a9ca4638
+ 2.0 en [optionalsettings,mod_assignment]
+ 2.0 en [requiregrading,mod_assignment]