What is it?

• Bugfix
• Feature
• Codebase improvement

Description of the changes in your PR

• Added possibility to set own sorting for each checklist.
  • Reused customSorting logic from Commons.
  • Because it's called customSorting in other apps, and "custom sorting" means something different here, I've created helpers with the name ownSorting.
  • Sorting is applied both inside the app and for widgets.
• Refactored moveDoneChecklistItems to be part of config.sorting, so it's also possible to set it separately for each checklist.
  • Added it as another flag to config.sorting, similarly as showing items count has been done in Gallery's grouping options.
  • To not lose users settings, I've created a migration, that is run only once. It copies the moveDoneChecklistItems value to be a flag in a current config.sorting.
• Additionally, it fixes two bugs:
  • Moving checked items to the bottom for custom sorting in OpenNoteDialog (reported in Improvement of the overview screen #83).
  • The same bug as above, but in widgets (not reported).

Before/After Screenshots/Screen Record

Fixes the following issue(s)

• Fixes Sort by feature for each Note #81
• Fixes Improvement of the overview screen #83

Acknowledgement

• I read the contribution guidelines.