Author: Damyon Wiese
MDL-52838 workshop: Each criterion > 0 levels
Add validation to the edit assessment form so each criterion in a rubric requires at least one level.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=eecc7ff3726696fbeee78525a510bb58ad4cc433
http://github.com/moodle/moodle/commit/eecc7ff3726696fbeee78525a510bb58ad4cc433
+ 3.2 en [mustdefinelevel,workshopform_rubric]