unregister before confirmation of vagrant destroy

[ansiblejunky]

The plugin appears to unregister the machine before the user gets prompted to confirm whether or not we really want to destroy the machine. See the output below. This happens only when the machine is running. When it is shutdown and then destroyed it seems fine.

> vagrant destroy tower1
==> tower1: Unregistering box with vagrant-registration...
    tower1: Are you sure you want to destroy the 'tower1' VM? [y/N] y
==> tower1: Forcing shutdown of VM...
==> tower1: Destroying VM and associated drives...

The plugin should never post any messages before the prompt. After confirmation, it should unregister the box.