Update freemodbus component file esp-idf/components/freemodbus/port/portserial.c to remove UART mode settings;
Move UART mode settings into esp-idf/examples/protocols/modbus_slave/main/freemodbus.c
Move UART pin settings from Component config into example Kconfig.projbuild file
Move setup of UART port pins from freemodbus component into example file
TW#27721
Closes https://github.com/espressif/esp-idf/issues/2784#issuecomment-443600157
This example adds functionality to support basic communication in RS485 networks using Modbus protocol.
This example uses FreeModbus stack and regular UART driver API to communicate in RS485 half duplex mode.
Added initial support of modbus controller pure C api to access device parameters over Modbus transport.
Move freemodbus stack and port files into components folder
Move the modbus_controller interface into components idf folder
Source files updated after review.
Add modbus interface documentation docs/en/api-reference/protocols/modbus.rst
porttimer.c: fix bug with timer1 selected in the Kconfig
Add support of cmake system (added cmake files)
Closes https://github.com/espressif/esp-idf/issues/858
