Merge pull request #240 from ramielrowe/drop_delete_end_no_launched_at

Drop delete.end notifications with blank launched_at
Better handling of resize issues

Populating flavor details from prep.end turns out to be a bit
too early. If the compute is restarted before the resize has
finished the instance will still be the old size. Thus, an exist
after that will be for the old (and actual) size of the instance.