Ember - donation system, bans, loading screen & landing/index page

1. Group sync improvements
2. Added a field for in-game group names to group settings (to allow for different display names)
3. Existing CAMI (ULX etc.) groups are now synced into Ember groups
4. Sync for revoked groups has been reinstated
5. Other minor improvements

Files modified:

1. lua/ember/lua/ember/store.lua
2. web/app/Controllers/MigrationController.php
3. web/app/Controllers/ServerApiController.php
4. web/app/Events/GroupSaving.php
5. web/app/Models/Group.php
6. web/app/Models/User.php
7. web/package-lock.json
8. web/package.json
9. web/public/css/app.css
10. web/public/js/adminvue.js
11. web/public/js/app.js
12. web/public/mix-manifest.json
13. web/resources/js/app.js
14. web/resources/sass/app.scss
15. web/resources/views/admin/features.twig
16. web/resources/views/admin/groups.twig
17. web/resources/views/admin/loadingscreens.twig
18. web/resources/views/admin/packages.twig
19. web/resources/views/dependencycheck.twig
20. web/resources/views/templates/app.twig