Presenter for WorldwideOfficeAppointment

Quacks like a RolePresenter so it can be used in the people/person
partial without modificiation.
Validate WorldwideOfficeAppointment associations
WorldwideOffice cleansup appointments
reword tests
Rework managing WorldwideOfficeAppointments

Instead of creating the people, we now work with appointments
directly. This workflow feels more natural
Revert weird embedded appointments in people form
Make workflow easier by not requiring person

You can create a WorldwideOfficeAppointments without an associated
Person. This makes it easier for editors to add the appointments
first and people later, as well as vice versa