Clarification request concerning `choosenim_install`
The readme has this example to auto-install the Nim compiler for source distributions, which is nice for providing code to those who don't have Nim installed.

```python
setup(
    ...,                            # Keep your existing arguments
    package_data={'': ['*.nim*']},  # Distribute *.nim & *.nim.cfg source files
    # include_package_data=True,    # <- This line cannot work with package_data
    install_requires=[
        'nimporter',  # Must depend on Nimporter
        'choosenim_install'  # Optional. Auto-installs Nim compiler
    ]
)
```

However, I cannot seem to get this to work (in a fresh environment without the Nim compiler).

A `pip install -e .` or `python setup.py develop` and `nimporter build [package name]` results in: 

`FileNotFoundError: [Errno 2] No such file or directory: 'nimble'`

This is on both Windows and Linux (Ubuntu).

Am I doing something wrong here?