Added additional information to the Sphinx documentation and module docstrings. No functional changes were made since the last release. Thanks jposada202020!
To use in CircuitPython, simply install the [Adafruit CircuitPython Bundle](https://circuitpython.org/libraries).
To use in CPython, `pip3 install adafruit-circuitpython-mcp230xx`.
Read the [docs](http://circuitpython.readthedocs.io/projects/mcp230xx/en/latest/) for info on how to use it.