Implement vertical label.
Open product change matrix dialogs.
Fix product change standard loading and saving.
Complete product change standard matrix.
Tune layout of the product chaneg standard matrix.
Handle None as the current area.
Add tests for area descendant and ancestor.
Add failing test for a new getTrail().
Implement Area.getTrail().
Show area trails.
Add work topic filtering.
Enable work topic sorting.
Set work topic alignment role.
Start implementing the product change model.