Use Intel TXT for remote validation of clusters

[geofft]

The Dell 790s (at least) have Intel processors that support  TXT, which can use some combination of the  TPM and virtualization / IOMMU support to do remote attestation. That way we can verify that the bootloader, the kernel, the public workstation verification script, and anything it depends on have not been tampered with, and thereby trust the results of the verification script.

[geofft]

Intel  recently announced a thing called  OpenAttestation, which might make this more tractable.