Set .version-suffix properly when building from Git
nixos-rebuild: Let --help invoke "man nixos-rebuild"
nixos-rebuild: Document --profile-name
Map --help flag to "man <command>" for more NixOS commands
Drop <services> from $NIX_PATH
Refactor variable names
Remove unused file
Rename nixos-hardware-scan to nixos-generate-config
nixos-generate-config: Write to /etc/nixos/hardware.nix rather than stdout
Typo
Merge "nixos-option --install" into nixos-generate-config

Having configuration.nix generation hidden underneath nixos-option
never made sense, also given that there was another command to
generate part of the configuration (nixos-hardware-scan).  Now
nixos-generate-config produces both configuration.nix and
hardware-configuration.nix.  The latter is overwritten while the
former is not.
Use read_file from File::Slurp
nixos-generate-config: Generate swapDevices
nixos-generate-config: Emit fileSystems automatically
nixos-generate-config: Skip FUSE filesystems

I don't know how to recover that a FUSE filesystem is (say) ntfs-3g.
nixos-generate-config: Emit boot.initrd.availableKernelModules instead of kerneLmodules
nixos-generate-config: Add --root option

If this option is given, nixos-generate-config will write the
configuration to /etc/nixos under the given root, and only emit
fileSystems attributes for filesystems under the given root directory.

The typically use case is at installation time, where you can say:

  $ nixos-generate-config --root /mnt

which will create /mnt/etc/nixos/{configuration.nix,hardware-configuration.nix}.

Also add a --force flag to force overwriting configuration.nix.
Document nixos-generate-config
Document nixos-install
Load the xfs kernel module on demand