Supervisor serials

[umbernhard]

If one supervisor is online, and connected to another machine, say, a Votebox, and another supervisor comes online with the same serial as the first, the network has no way of distinguishing the two. As of right now, both can close and open polls, generate PINs, and issue ballots. We need to figure out how to fix this. It may have to do with adding some checks in Auditorium itself, or inside each machine's network connector.

[umbernhard]

Once we have TPM fully implemented, this problem should go away since the serial will be linked into the attested state of the program as it comes online.