importance is only implemented for groups and lists. Implement this for all types! This is only about adding the class according to the semantics, styling is a separate issue.
1. Importance in semantics should be reflected in editor for all types
2. Create function for creating label, description and wrapper (so it might be used by widgets)
3. Update createFieldMarkup to use these helper functions
4. Double check that none of the functions duplicate the markup.