Use individual directly

This removes most of the Contact class and uses directly the Individual of folks. This refactors a lot of code and makes it more readable, because the added level the Contact class add was removed. This also cleans up how linking was done, by using directly the linking methods of folks. This makes the FakePersona be a real Persona which stores data till folks returns the actually Persona. The FakePersona could also be used later as a storage for modified properties will in edit mode, which then can be transferred to the real Persona.