Made table data source issue row moves when possible during object moves

Even though the documentation for NSFetchedResultsControllerDelegate suggests that you should delete & insert rows when an object moves position, it is possible to make a move command most times. This makes for a more representative animation.

As long as you're not trying to move a row from a section that is about to be deleted, or to one that is about to be inserted, it's all fine. I've reported a [radar](http://openradar.appspot.com/17684030) on the issue too, dupe if you like :)