77d8988b7b
When using a modified systemd-package (e.g. to test a patch), it's recommended to use the `systemd.package`-option to avoid rebuilding all packages that somehow depend on systemd. With this change, the modified package is also used by `systemd-nspawn@` units.
*** NixOS *** NixOS is a Linux distribution based on the purely functional package management system Nix. More information can be found at http://nixos.org/nixos and in the manual in doc/manual.