Author: Rossiani Wijaya
MDL-27161: fixed optional setting for 'require grading' to prevent page lock out (head)
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e512715b8983b8b71126d0978051006c52a369fa
http://github.com/moodle/moodle/commit/e512715b8983b8b71126d0978051006c52a369fa
+ 2.1 en [norequiregrading,mod_assignment]
+ 2.1 en [nosubmisson,mod_assignment]