Updated README for first release

[jeffcogswell]

Updated readme with examples for getting started.

More coming soon but this is the start.

[brianmcgee]

Some nits, some aesthetic things to keep everything consistent.

[jfroche]

Maybe we can make something more basic like in one file ?

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    system-manager = {
      url = "github:numtide/system-manager";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs =
    {
      self,
      nixpkgs,
      system-manager,
    }:
    {
      systemConfigs.default = system-manager.lib.makeSystemConfig {
        modules = [
          (
            { config, pkgs, ... }:
            {
              nixpkgs.hostPlatform = "x86_64-linux";
              environment.systemPackages = with pkgs; [
                btop # Beautiful system monitor
                bat # Modern 'cat' with syntax highlighting
              ];
            }
          )
        ];
      };
    };
}

[jeffcogswell]

Originally I did it this way, but somebody else in the project suggested I break it up so that the default.nix file bears some resemblance to what we use over in NixOS. I'm personally good with either, but not sure how to proceed... One person makes one suggestion, another person makes a different suggestion, and both seem equally good. 😄

[zimbatm]

Some small nits and then let's merge this. We can always do another pass later.

[zimbatm]

It looks like this variable isn't being used.

[zimbatm]

Is there a reason to not add it to the cli_tools.nix file?

[zimbatm]

This warning still applies.

[zimbatm]

We're trying to talk to a public that is not necessarily deep into Nix. I think the intro should talk to normal sysadmins. Why should they care about this tool? What is it?

System Manager is a tool to configure Linux machines.

Unlike Chef, Puppet and Ansible, it only controls a small subset, and most of its changes are done in an immutable layer, thanks to the power of Nix.

[zimbatm]

Let's move all the advanced examples in the doc once it exists.

Users coming in the README are mostly trying to:

1. Figure out if the project is for them. So quickly get an understanding of what the tool is, what are the features, what is the status of development.
2. Want to orient themselves: find the doc, how to contribute, that kind of things.

The getting started also acts of a selling pitch to illustrate what the tool can do, and why it's cool.