Adafruit-circuitpython-fona

This **breaking** release adds:
* Updated SMS receive mechanism
* Added Ring Indicator (RI) pin to fona initialization.
* Move to polling `receive_sms` mechanism instead of only polling the serial UART.
* `receive_sms` allows for optionally checking UART or RI for incoming SMS messages.
* Examples (`sms` & `sms_response`) updated
* **BREAKING**: Removed public access to uart serial functions (readline, uart write) from user-code
* Added compatibility for FONA3G Modules:
* New `fona_3g.py` child class, contains methods compatible with the SIMCom SIM5320 module's AT command set.
* `adafruit_fona_socket` queries and uses the SIM5320's tcp transmit timeout, socket writes now use user-set timeouts
* Examples updated and tested with FONA808 and FONA3G
* **Breaking**`adafruit_fona_network` class added for connecting and interacting with GSM and CDMA cellular networks.
* Note: This replaces the `GSM` class.

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-fona `.

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

This release adds:
* `fona_sms_response.py`: Example which waits for a SMS message from the FONA, reads it out and replies back to the sender. Similar to [FONA_SMS_Response.ino in the arduino fona library](https://github.com/adafruit/Adafruit_FONA/blob/master/examples/FONA_SMS_Response/FONA_SMS_Response.ino).
* `fona.enable_sms_notification`: Getter/setter properties for FONA sms notification command
* `fona.in_waiting`: Returns number of bytes available to be read from the uart (https://circuitpython.readthedocs.io/en/latest/shared-bindings/busio/UART.html#busio.UART.in_waiting)
* **NOTE**: The `_read_line()` method **has been changed to** `read_line()`

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-fona `.

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

This release adds:
* https://github.com/adafruit/Adafruit_CircuitPython_FONA/pull/4 SMS Functionality - Send and read SMS messages from CircuitPython!
* See [the fona_sms.py example for usage information](https://github.com/adafruit/Adafruit_CircuitPython_FONA/blob/master/examples/fona_sms.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-fona `.

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

This release adds:

**Compatibility**
* with `CircuitPython_MiniMQTT`, `CircuitPython_Requests`

**Methods**
* `reset`: performs a hardware reset on the modem
* `factory_reset`: factory reset modem
* `icccid`: rets. sim card's iccid number
* `unpretty_ip`

**Modules**
* `adafruit_fona_gsm`: Class for interfacing with 2G GSM modems (FONA808+GPS),
* Simpler user-code for attaching to, bringing up, and disconnecting GSM modem.
* Network connection and error handling is now handled from user-code instead of within the module (polling similar to ESP32SPI's `wifimanager`)

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-fona `.

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

This release adds:
* Compatibility for usage with the [Adafruit_Requests](https://github.com/adafruit/Adafruit_CircuitPython_Requests/) library
* New examples: Twitter Cheerlights, Adafruit IO HTTP Publish
* Updated `fona` module which increases network reliability and speed.

**NOTE:** This initial alpha version has not been tested with `CircuitPython_MQTT` or CircuitPython IOT SDK Libraries. Please report any bugs on the [issues page for this library](https://github.com/adafruit/Adafruit_CircuitPython_FONA/issues).

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-fona `.

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

This library provides hardware support for the Adafruit FONA cellular module. This library includes an interface for the cellular module (`adafruit_fona.py`) and a CPython `socket`-like interface (`adafruit_fona_socket.py`).

**NOTE:** This initial alpha version has not been tested with CircuitPython IoT libraries such as `CircuitPython_Requests` or `CircuitPython_MQTT`. Please report any bugs on the [issues page for this library](https://github.com/adafruit/Adafruit_CircuitPython_FONA/issues).

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-fona `.

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