Refactor validation so that it fires only on question_type change on edit.
Refactor validation so that it fires only on question_type change on edit.

2015SebINF1340/dmptool,derDaywalker/dmptool,derDaywalker/dmptool,derDaywalker/dmptool,derDaywalker/dmptool,2015SebINF1340/dmptool,2015SebINF1340/dmptool