qformat_multichoiceset

I have been asked several time by teachers how they can change some/all of their
multichoice questions into all or nothing (multichoiceset) questions.

This import format plugin takes a Moodle XML file and import all
regular multichoice questions changing them into all or nothing questions.

This enables users to export some of their multichoice questions
using the normal Moodle XML export format
and import them back with this format.

The additionnal benefit of this process is that they now have 2 copies of each question, one
using the regular grading scheme and one using the all or nothing grading scheme.

This plugin should go into the question/format/multichoiceset Moodle installation
directory. Login as admin to complete plugin installation. Then select
this format Import all or nothing format during question bank import.

This work is based on the crossxml qformat plugin made by Daniel Thies 2018 dethies@gmail.com and
licensed under the included GPL 3