Initial implementation.
Merge remote branch 'upstream/master' into add_spaced_list_type
Focus setting working.
Add tests for new list type.
Run startup checks on loading previewed app(s).
Merge pull request #1198 from arjclark/fix.preview_app_dup_check

rose edit: Run startup checks on loading previewed app(s).
Merge pull request #1195 from arjclark/add_spaced_list_type

rose metadata: Add spaced list type
Document spaced_list type.
Merge pull request #1199 from arjclark/doc.spaced_list

Document spaced_list type.