Author: Rossiani Wijaya
MDL-36905 accessibility for assignment grading: add label for grading actions and operations select options
http://git.moodle.org/gw?p=moodle.git;a=commit;h=49f0c151dd54a13ae39fcc6c1733251916a9805c
http://github.com/moodle/moodle/commit/49f0c151dd54a13ae39fcc6c1733251916a9805c
+ 2.4 en [choosegradingaction,mod_assign]
+ 2.4 en [chooseoperation,mod_assign]