There are 2 main reason for doing this:
1. Because I can, I wanted to see if I could do it
2. It gets rid of the janky qml re parenting stuff so should be faster.
Improve the behaviour of jump to last unread message. The view will now jump as high as possible if the last unread message isn't loaded. This at least triggers more items to load which will eventually get the user to the last unread message.
