Adafruit-circuitpython-rfm9x

This release includes:
* 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-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

* https://github.com/adafruit/Adafruit_CircuitPython_RFM9x/pull/33 `send` and `receive` methods modified to allow interrupts from user-code.
* [Example of usage with Raspberry Pi](https://github.com/adafruit/Adafruit_CircuitPython_RFM9x/blob/master/examples/rfm9x_rpi_interrupt.py)

* https://github.com/adafruit/Adafruit_CircuitPython_RFM9x/pull/33 `send` can now listen after a packet is sent using new kwarg `keep_listening`
* [Example of usage on Microcontrollers](https://github.com/adafruit/Adafruit_CircuitPython_RFM9x/blob/master/examples/rfm9x_transmit.py).

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-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

* Repo URL updated to the correct URL for compatibility with `circup`, thanks ntoll

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-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

* Incorrectly setting `tx_power` and `frequency_mhz` throws errors describing the accepted range
* RFM9x now checks version to verify correct wiring

Thanks terriko!

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-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

This release adds optional control properties to easily modify the modem's configuration. Thanks applio! 21

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-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.

Updated simpletest to blink on-board LED when packets are received.

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-rfm9x`.

Read the [docs](http://circuitpython.readthedocs.io/projects/rfm9x/en/latest/) for info on how to use it.