WIP: Transfer keys to newly added contact via key manager
This branch adds key manager methods for transferring keys from a pending contact to a contact. I started to take the wrong approach in !1107 (merged), so much of that code is replaced.
The branch also makes the key manager aware of PendingContactRemovedEvents, and fixes a null argument when updating keys for a pending contact.
Closes #1570 (closed)
Edited by akwizgran