Add dbus API for adding contact with preset properties

The API takes an array of (key, value) pairs.

Supported keys: This can be specified multiple times "email-addresses", "notes", "phone-numbers" Only the last will be stored (because this properies are unique) "alias", "full-name", "nickname"

Not all properites are supported for now because they can't be easily set via dbus because they arn't a string

The API can be used via gdbus as well gdbus call --session --dest org.gnome.Contacts --object-path /org/gnome/Contacts --method org.gtk.Actions.Activate 'new-contact-data' '[<[("email-addresses", "julian@sparber.net"), ("phone-numbers", "+39333333"), ("email-addresses", "secondo@example.com")]>]' '{}'

Upstream MR: https://gitlab.gnome.org/GNOME/gnome-contacts/merge_requests/95

Fixes #22 (closed)