Upgrade Handoff and modify some problems

[ellis-wu]

I upgrade Handoff, add the following items as follows:

1. Handoff API add Neutron, allowing the user to specify the destination of the Neutron network.
2. The Nova Image API is deprecated, so I updated it and used the Glance API.

And Updated some of the problems that Neutron will encounter:

1. Dettach NIC before Create Overlay.
2. Dettach NIC before Handoff.
3. Determine if there is a NIC in the VM XML