Fixed issue where `ZeroDivisionError` would be raised in sparkline if autorange was set and only identical values were added.
To use in CircuitPython, simply install the [Adafruit CircuitPython Bundle](https://circuitpython.org/libraries).
To use in CPython, `pip3 install adafruit-circuitpython-display-shapes`.
Read the [docs](http://circuitpython.readthedocs.io/projects/display-shapes/en/latest/) for info on how to use it.