* build01: add initial nixpkgs-update configuration
* use niv for nixpkgs-update
* nixpkgs-update: now it works!
Having to make r-ryantm a normal user is lame, but `hub` needs a
regular home directory to work. Eventually I should move away from
using hub. The XDG_CONFIG env variables are because nixpkgs-update
doesn't detec the systemd XDG-like env variables yet.
* nixpkgs-update: add r-ryantm as trusted user and logging config
* nixpkgs-update: add cachix
* nixpkgs-update: update with niv
* nixpkgs-update: fixup cachix config
