Author: Marina Glancy
MDL-50586 gradingform_rubric: warn about missing 0-points levels
http://git.moodle.org/gw?p=moodle.git;a=commit;h=c9958ef01504b9b3df45d21442023907d07ca155
http://github.com/moodle/moodle/commit/c9958ef01504b9b3df45d21442023907d07ca155
+ 3.1 en [err_novariations,gradingform_rubric]
+ 3.1 en [zerolevelsabsent,gradingform_rubric]