[Nix-dev] Aarch64!

[Graham Christensen]

Vladimír's email reminded me I hadn't said anything about aarch64...
but, many people already know :)

As of yesterday, with the excellent help of Tuomas (Dezgeg) and others,
plus the generous donation of 96-core Cavium ThunderX machines from
Packet.net, we now have Nixpkgs unstable building Aarch64 packages!

These should run just fine on Raspberry Pi 3, and of course,
Packet.net's ThunderX machines.

I added it first to nixpkgs only in order to "smoke test" the deployment
without interrupting NixOS. I have no objection to moving it over to
NixOS itself, the machines should be able to run the NixOS tests just
fine.

Currently, we only have one Aarch64 builder. We can add more, and having
Hydra building stdenv will make the provisioning process much faster.

Let us all celebrate this big milestone, and push forward to NixOS on
ARM!

Thank you to Tuomas, nathan7, Eelco, Packet.net, and all the ARM
contributors for making this possible.

Thank you,
Graham Christensen