Moodle 4.5 and PHP 8.3

Moodle 4.5 compatibility. Confirmed PHP 8.3 compatibility.

v2.140

Version bump for deployment purposes

v2.139

PHP 8.2 and Moodle 4.4 compatibility

PHP 8.1 deprecation and letterhints on upgrade

Fix for PHP 8.1 deprecation messages.
Re-instate the creation of letterhints field in the db for upgrades from before v1.97 (in 2018).

Darktheme on mobile and long answers

Fix compatibility on mobile with dark theme (css tweak) #100

Centre droptarget text to better handle long answers #99

Additional English language sample questions.

remove html comments from rendered output

Remove html comments from code before rendering. There is no reason to include comments at run time and when people copy and paste from other sources it can include items like <!--[if !supportLists] creating spurious gaps. Thanks to sunnac for reporting this.

New behat test to confirm core mlang and mlang2 filters work as expected.

Additional English language sample questions.

HTML5 dragdrop

jquery-ui was breaking Moodle 4X interface. Move to HTML5 dragdrop, which has become the standard

Duplicate draggables in mobile

Fixed duplicate draggables in mobile and no mobile css where Moodle was in a folder off the domain.

Moodle 4.0 Compatibility

Update tests to work with Moodle 4.0. End of MS IE11 support. Fix for multiple correct answers with i18n

v2.139_02

Need new version to deploy to moodle.org/plugins