add multi register area descriptors into concrete port (initial)
add create/destroy of area descriptors into concrete port
add the list of descriptors in common slave interface structure and init/destroy in concrete slave port
move r/w callback functions into common slave
final update of common slave interface wrappers add override API option in concrete port
update slave examples to check new feature
* Original commit: espressif/esp-idf@96b77a28b1
Add TCP port files to provide Modbus TCP interface for communication
Add freemodbus add tcp support for common master/slave iface and tcp example based on socket API
The communication between master and slave checked for each example serial_master, serial_slave (use ModbusPoll TCP)
update tcp example according netif changes, fix ci issues
update TCP slave implementation
update example_test.py to to set IP through stdin
update API documentation
event bit instead of semahore to lock communication resource
update default options and master/slave port files
Closes https://github.com/espressif/esp-idf/issues/858
Closes IDF-452
* Original commit: espressif/esp-idf@d0b9829eef