Add support for NixOS + Fedora, Arch, RH minor changes (#195)

* Add support for NixOS

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* updated files for immutable root fs

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* update ssh key location

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* change initrd host key name

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* add missing -p switch

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* comments about SSH and encrypted bpool

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* backup hardware-configuration.nix file

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* clearer wording for backup

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* global useDHCP flag is deprecated

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* point user to configuration.nix

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* fixes for systemd-autofs; network; typo

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* force command to return 0

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* fix command to postMount

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* fix mount command

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* escape $i

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* create mountpoints before booting

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* replace postDevice,preMount command

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* disable zfs-mount

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

* generate machine-id

Signed-off-by: Maurice Zhou <jasper@apvc.uk>

docs/Getting Started/NixOS/Root on ZFS.rst

@@ -0,0 +1,11 @@
+NixOS Root on ZFS
+=======================================
+`Start here <Root%20on%20ZFS/0-overview.html>`__.
+
+Contents
+--------
+.. toctree::
+  :maxdepth: 2
+  :glob:
+
+  Root on ZFS/*