931b7b47a2
This fixes some quirks I introduced in previous commits. 1. No need for an extra newline when printing the output of shell commands. 2. 'or die' is what's already used in the NixOS test sources, while 'die unless' has no occurrences.
To build the manual, you need Nix installed on your system (no need
for NixOS). To install Nix, follow the instructions at
https://nixos.org/nix/download.html
When you have Nix on your system, in the root directory of the project
(i.e., `nixpkgs`), run:
nix-build nixos/release.nix -A manual.x86_64-linux
When this command successfully finishes, it will tell you where the
manual got generated.