WIP: Report to listeners when the potential address resolution changes

For resolved phone numbers, the resolution may change when there is a new match added or removed for the minimized number form.
It may be better to report any removal as a potential resolution change; we would have to look at the client code in libcommhistory.

Note: test does not work, because events are not being processed by the cache.  We would need to alter the test to permit this, or provide a hook so the test can invoke the necessary updates in the cache.