[timz]

Added support for dependency between commands. So one can now write:

    # [clean]() Clean build directory

    ```bash
    rm -rf ./build
    ```    

    # [format]() Format the source code

    ```bash
    npx prettier --write .
    ```

    # [build](clean format) Build the project

    ```bash
    npm run build
    ```

    # [deploy](build) Deploy to surge.sh

    ```bash
    surge ./build my-project.surge.sh
    ```

This doesn't include file time modification between files as in Makefile.

Thank you for feature suggestion.