Amodbus

-------------
* Support Modbus TLS (client / server)
* Distribute license with source
* BinaryPayloadDecoder/Encoder now supports float16 on python3.6 and above
* Fix asyncio UDP client/server
* Minor cosmetic updates
* Asyncio Server implementation (Python 3.7 and above only)
* Bug fix for DiagnosticStatusResponse when odd sized response is received
* Remove Pycrypto from dependencies and include cryptodome instead
* Remove `SIX` requirement pinned to exact version.
* Minor bug-fixes in documentations.

-------------
* Support Python 3.7
* Fix to task cancellations and CRC errors for async serial clients.
* Fix passing serial settings to asynchronous serial server.
* Fix `AttributeError` when setting `interCharTimeout` for serial clients.
* Provide an option to disable inter char timeouts with Modbus RTU.
* Add support to register custom requests in clients and server instances.
* Fix read timeout calculation in ModbusTCP.
* Fix SQLDbcontext always returning InvalidAddress error.
* Fix SQLDbcontext update failure
* Fix Binary payload example for endianess.
* Fix BinaryPayloadDecoder.to_coils and BinaryPayloadBuilder.fromCoils methods.
* Fix tornado async serial client `TypeError` while processing incoming packet.
* Fix erroneous CRC handling in Modbus RTU framer.
* Support broadcasting in Modbus Client and Servers (sync).
* Fix asyncio examples.
* Improved logging in Modbus Server .
* ReportSlaveIdRequest would fetch information from Device identity instead of hardcoded `amodbus`.
* Fix regression introduced in 2.2.0rc2 (Modbus sync client transaction failing)
* Minor update in factory.py, now server logs prints received request instead of only function code

-------------
* Fix Issues with Serial client where in partial data was read when the response size is unknown.
* Fix Infinite sleep loop in RTU Framer.
* Add pygments as extra requirement for repl.
* Add support to modify modbus client attributes via repl.
* Update modbus repl documentation.
* More verbose logs for repl.

-------------
* Fix unicode decoder error with BinaryPayloadDecoder in some platforms
* Avoid unnecessary import of deprecated modules with dependencies on twisted

-------------
* Async client implementation based on Tornado, Twisted and asyncio with backward compatibility support for twisted client.
* Allow reusing existing[running] asyncio loop when creating async client based on asyncio.
* Allow reusing address for Modbus TCP sync server.
* Add support to install tornado as extra requirement while installing amodbus.
* Support amodbus REPL
* Add support to python 3.7.
* Bug fix and enhancements in examples.
* Async client implementation based on Tornado, Twisted and asyncio

-------------
* Fix serial client `is_socket_open` method