Adafruit-circuitpython-circuitplayground

* Added support for touch, `play_tone`, `start_tone`, `stop_tone`, acceleration.
* Library is now imported as: `from adafruit_circuitplayground.express import cpx`
* Docs and examples updated.

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

Read the [docs](https://circuitpython.readthedocs.io/projects/circuitplayground/en/latest/adafruit_circuitplayground/index.html) for info and examples.

A sphinx check broke the load on actual devices. This release fixes it.

This doesn't support everything on the board but its a start. This is a release so it can be added into the bundle.