Added NixOS Tools.

Added NixOS on WSL to NixOS Tools and Modules.

README.md

@@ -327,6 +327,12 @@
  
  - [NixOS on WSL](https://github.com/nix-community/NixOS-WSL) is a minimal root filesystem for running NixOS on WSL. It can be used with DistroLauncher as ```install.tar.gz``` or as input to ```wsl --import --version 2```.
  
+ - [Appvm](https://github.com/jollheef/appvm) is a simple application VMs (hypervisor-based sandbox) based on Nix package manager. It uses one read-only /nix directory for all appvms. So creating a new appvm (but not first) is just about one minute.
+
+ - [Deadnix](https://github.com/astro/deadnix) is a tool that scan ```.nix``` files for dead code (unused variable bindings).
+
+ - [nix2container](https://github.com/nlewo/nix2container) isa tool that provides an efficient container development workflow with images built by Nix: it doesn't write tarballs to the Nix store and allows to skip already pushed layers (without having to rebuild them).
+
 ## NixOS Desktop
 [Back to the Top](https://github.com/mikeroyal/NixOS-Guide#table-of-contents)