Cleanup Contacts.Typeset
One of the more special constructions in GNOME contacts is with the different types of properties of a contact. Due to the strange way of mapping a (set of) VCard types, custom labels (e.g. by Google) and custom labels, we have to deal with a lot of edge cases.
This MR tries to simplify the internals of the Typeset a bit, in the hope that we can iteratively improve this in the 3.31 series.