Pymodbustcp

- fix ModbusServer: wrong check of input registers length in DataBank (thanks to monsieurvor).
- improve hostname validation in utils (thanks to MCXIV and schmocker).
- experimental add of read_device_identification() (over modbus encapsulated interface) to client and server.
- experimental add of write_read_multiple_registers() function (code 0x17) to client and server (thanks to tanj).
- updated compatibility test (python versions): remove 3.5/3.6, add 3.11.

- ModbusClient: parameters are now properties instead of methods (more intuitive).
- ModbusClient: now TCP auto open mode is active by default (auto_open=True, auto_close=False).
- ModbusClient: add custom_request method for send user define PDU to modbus server.
- ModbusClient: remove RTU mode.
- ModbusClient: clarify some things (private methods and internal vars rename).
- ModbusServer: big redesign to improve readability and maintainability.
- ModbusServer: no longer use hard linked class DataBank (it now return a deprecation warn).
- ModbusServer: add of ModbusServerDataHandler and DefaultDataBank class for easy customize.
- add or update server examples for new modbus server design.
- some updates on tests, fix random arrays generation on client test part.
- clarify usage of root privilege for open tcp/502 (avoid Errno 13) in server example.
- python 2 end of support.

- word_list_to_long() and long_list_to_word(), now support 64 bits long long with opt long_long.
- encode_ieee() and decode_ieee(), now support double-precision format with opt double.
- add shortcut alias for functions with long names in utils.
- rewrite of some functions in utils.
- improve test_utils readability.
- server DataBank enforce type check on set data methods to avoid server crash (thanks to xuantw).
- now get_2comp can deal with negative python int.
- remove reference to devel github branch.
- improve last_error_txt() and last_except_txt().

- add module error MB_SOCK_CLOSE_ERR (occur if frame send on close socket).
- add modbus exception EXP_NEGATIVE_ACKNOWLEDGE (code 0x07) to constants.
- add last_error_txt() and last_except_txt() for produce human readable status.
- add EXP_TXT, EXP_DETAILS and MB_ERR_TXT dicts to constants (text representation of codes).
- update of the compatibility test for python version: remove 2.6/3.2/3.3, add 3.7/3.8/3.9.
- conform to PEP 396 (add pyModbusTCP.__version__ field).

- fix ModbusServer: avoid hard coded TCP port (thanks to akobyl).
- add stop() and is_run property to ModbusServer (thanks to Rugiewitz).

- fix ModbusServer issue on Windows (thanks to andreascian).