[Cryptech Core] Upgrading bikeshed.cryptech.is

[Rob Austein]

bikeshed.cryptech.is requires an operating system upgrade (old version
is at EOL).  This is a major version bump, so a bit more involved than
the minor version bumps I've been doing all along without anybody
noticing.  Yes, of course we have backups.

I've started the process, will send mail when done or if I need to
take externally visible services down for more than a few minutes.