message: docs(CLI): add installation instructions
diff: @@ -8,28 +8,64 @@ even used from a script.
  In fact, the Etcher desktop application is simply a wrapper around the CLI,
  which is the place where the actual writing logic takes place.
  -Running
  --------
  +Installing
  +----------
  -We are not oficially releasing the Etcher CLI as a separate package yet, but
  -you can run it locally with the following steps:
  +Head over to [etcher.io][etcher] and download the package that corresponds to
  +your operating system.
  -- Clone the Etcher repository.
  +macOS and GNU/Linux
  +-------------------
  +- Extract the `.tar.gz` package by running:
  +
  +```sh
  +tar fvx path/to/cli.tar.gz
  ```
  -git clone https://github.com/resin-io/etcher
  -```
  -- Install the dependencies by running:
  +- Move the resulting directory to `/opt/etcher-cli`
  +
  +- Add `/opt/etcher-cli` to the `PATH`. For example, add the following to
  + `.bashrc` or `.zshrc`:
  ```sh
  -npm install
  +export PATH="$PATH:/opt/etcher-cli"
  ```
  -- Run the Etcher CLI from `bin/etcher`.
  +Windows
  +-------
  -```
  -./bin/etcher --help
  +- Unzip the `.zip` package by right-clicking on it and selecting "Extract All"
  +
  +- Move the resulting directory to `C:\etcher-cli`
  +
  +- Add `C:\etcher-cli` to the `%PATH%`
  +
  + - On Windows 10 and Windows 8
  + - Open *Control Panel*
  + - Open *System
  + - Click the *Advanced system settings* link
  + - Click *Environment Variables*
  + - Find the `PATH` environment variable, and click *Edit*
  + - Append `;C:\etcher-cli` to the environment variable value
  + - Click *OK*
  +
  + - On Windows 7
  + - Right-click the *My Computer* icon
  + - Open the *Properties* menu
  + - Open the *Advanced* tab
  + - Click *Environment Variables*
  + - Find the `PATH` environment variable, and click *Edit*
  + - Append `;C:\etcher-cli` to the environment variable value
  + - Click *OK*
  +
  + - Re-open `cmd.exe`, or PowerShell
  +
  +Running
  +-------
  +
  +```sh
  +etcher -v
  ```
  Options
  @@ -49,3 +85,5 @@ Debug mode
  You can set the `ETCHER_CLI_DEBUG` environment variable to make the Etcher CLI
  print error stack traces.
  +
  +[etcher]: https://etcher.io/
  