* Add support of loopback interface and a new connection type "loopback". On D-Bus,
  the loopback interface now has the "org.freedesktop.NetworkManager.Device.Loopback"
  interface instead of org.freedesktop.NetworkManager.Device.Generic".
  Loopback handling is special in that when the NetworkManager profile is
  deactivated, the interfaces will still be up and configured with a 127.0.0.1
  address.