Adafruit-circuitpython-tsl2591

* Update for removal of `stop` kwarg. ([more info](https://github.com/adafruit/circuitpython/issues/2082))

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

To use in CPython, `pip3 install adafruit-circuitpython-tsl2591`.

Read the [docs](http://circuitpython.readthedocs.io/projects/tsl2591/en/latest/) for info on how to use it.

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

To use in CPython, `pip3 install adafruit-circuitpython-tsl2591`.

Read the [docs](http://circuitpython.readthedocs.io/projects/tsl2591/en/latest/) for info on how to use it.

Uses `maxCounts` to determine if sensor overflowed.

Also update to `.pylintrc`.

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

To use in CPython, `pip3 install adafruit-circuitpython-tsl2591`.

Read the [docs](http://circuitpython.readthedocs.io/projects/tsl2591/en/latest/) for info on how to use it.

- Added `setup.py`
- Added PyPI release info to `.travis.yml`
- Updated `requirements.txt`
- Added a more comprehensive `.gitignore`

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-tsl2591`.

Read the [docs](http://circuitpython.readthedocs.io/projects/tsl2591/en/latest/) for info on how to use it.

Thanks to caternuson for adding examples

To use in CircuitPython, download the .mpy file and copy it to the `lib` folder on the `CIRCUITPY` drive. Or, simply install the [Adafruit CircuitPython bundle](https://github.com/adafruit/Adafruit_CircuitPython_Bundle).

Read the [docs](http://circuitpython.readthedocs.io/projects/tsl2591/en/latest/) for info on how to use it.

Thanks tannewt for the great work!