Adafruit-circuitpython-il0373

This release includes:
* Fixed an issue that occurred when passing `black_bits_inverted` or `color_bits_inverted` keyword arguments
* Migrating this repository from Travis to GitHub Actions. This has no effect on the behavior of the code itself.

To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://circuitpython.org/libraries).

To use in CPython, `pip3 install adafruit-circuitpython-il0373`.

Read the [docs](http://circuitpython.readthedocs.io/projects/il0373/en/latest/) for info on how to use it.

Added 2.9" Tri-Color eInk Example

To use in CircuitPython (version 5 or higher), simply install the [Adafruit CircuitPython bundle](https://github.com/adafruit/Adafruit_CircuitPython_Bundle).

Read the [docs](http://circuitpython.readthedocs.io/projects/il0373/en/latest/) for info on how to use it.

Initial release for use with CircuitPython 5+. Thanks tannewt

To use in CircuitPython (version 5 or higher), simply install the [Adafruit CircuitPython bundle](https://github.com/adafruit/Adafruit_CircuitPython_Bundle).

Read the [docs](http://circuitpython.readthedocs.io/projects/il0373/en/latest/) for info on how to use it.