Updated armband

Updated armband
Project: fuel  f09f2e3c661b8fcb1c82151e1ad17eea7275b417

VirtualFuel: Add temp_dir and vm_name attributes

These two variables are defined in one of the methods right now. They
will be useful to other methods too, so we add them as attributes to the
object here.

Signed-off-by: Josep Puigdemont <josep.puigdemont@enea.com>
virtual_fuel: make vm_template an attribute

Signed-off-by: Josep Puigdemont <josep.puigdemont@enea.com>
virtual_fuel: factor out image creation into a method

Signed-off-by: Josep Puigdemont <josep.puigdemont@enea.com>