Provide `marcosnils/bin` as an alternate installation method

[yozachar]

bin can grab proper luet version from https://github.com/mudler/luet/releases.

So in the README.md you can have:

## Install

- **Using official installer script:**

    ```console
    $ curl https://luet.io/install.sh | sudo sh
    ```

- **Or using [`bin`](https://github.com/marcosnils/bin)**

    ```console
    $ bin i github.com/mudler/luet
    ```

### Test installation:

```console
$ luet --help
$ luet search ...
$ luet install ..
.```

---

Preview

Install

• Using official installer script:

  $ curl https://luet.io/install.sh | sudo sh

• Or using bin

  $ bin i github.com/mudler/luet

Test installation:

$ luet --help
$ luet search ...
$ luet install ..

---

Are PRs on this welcome?

[Itxaka]

hat bin tihng is pretty handy, sure will help me manage my 100 of binaries downloaded from github! I would say a PR to add would be very helpful!