Design fixes for global search

See merge request AlekSIS!225

Resolve "Global search"

Closes #208

See merge request AlekSIS!204

- Use chips instead of checkboxes
- Show message if no search term is given

Resolve "Re-add django-dbbackup"

Closes #225

See merge request AlekSIS!223

Resolve "ugettext_lazy deprecated"

Closes #224

See merge request AlekSIS!222

Resolve "Add CSS/JS static files for material select2"

Closes #222

See merge request AlekSIS!219

Currently translated at 13.8% (35 of 254 strings)

Translation: AlekSIS/AlekSIS
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis/la/

Currently translated at 91.3% (232 of 254 strings)

Translation: AlekSIS/AlekSIS
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis/de/

Currently translated at 91.3% (232 of 254 strings)

Translation: AlekSIS/AlekSIS
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis/de/

Currently translated at 91.3% (232 of 254 strings)

Translation: AlekSIS/AlekSIS
Translate-URL: https://translate.edugit.org/projects/aleksis/aleksis/de/

Fixed mixed up JS/CSS in ANY_JS, turned off DEBUG

Fixed mixed up JS/CSS in ANY_JS, turned off DEBUG

Fix group sync

See merge request AlekSIS!221

Resolve "Add celery worker, celery-beat worker and celery broker to docker-compose.yml"

Closes #198

See merge request AlekSIS!216

Add yarn dependency "select2-materialize" in settings.py so that select2-materialize statics can be accessed from everywhere

Resolve "Synchronise AlekSIS groups with Django groups"

Closes #221

See merge request AlekSIS!214