Fixed issue with specifying a folder other than `"/"` for the images.
To use in CircuitPython, simply install the [Adafruit CircuitPython bundle](https://github.com/adafruit/Adafruit_CircuitPython_Bundle).
To use in CPython, `pip install adafruit-circuitpython-slideshow`.
Read the [docs](http://circuitpython.readthedocs.io/projects/slideshow/en/latest/) for info on how to use it.