add OVF file for admin appliance

This was generated manually in VirtualBox and then exported as OVF.
add metadata.json
metadata.json: change vdisk size to 16GB
import Vagrantfile created via `vagrant package`
box/Vagrantfile: add comment about fixing second MAC address
automate building of boxes from vmdk built by kiwi
initial stab at a multi-VM Vagrantfile for the whole cloud
add mysterious box metadata which isn't metadata.json

This is as described at http://docs.vagrantup.com/v2/boxes/format.html
but the nature of this file is still unclear:

  https://github.com/mitchellh/vagrant/issues/3613

So I'm not yet sure what we need this for, if anything.