Add support for selecting child services of selected services.
Add support for selecting child services of selected services.

Choosing a descendant of a service already in the cart removes
the selected ancestor of the service and replaces it with
the more precise descendant service.

vaaralav/servicemap,Zeukkari/servicemap,vaaralav/servicemap,City-of-Helsinki/servicemap,City-of-Helsinki/servicemap,Zeukkari/servicemap,vaaralav/servicemap,City-of-Helsinki/servicemap