Renamed the GPIO blink example to be a `simpletest` example in order to be consistent across the repositories. Thanks prcutler!
To use in CircuitPython, simply install the [Adafruit CircuitPython Bundle](https://circuitpython.org/libraries).
To use in CPython, `pip3 install adafruit-circuitpython-tca8418`.
Read the [docs](http://circuitpython.readthedocs.io/projects/tca8418/en/latest/) for info on how to use it.