Implement semaphore and mutex to safeguard the ISR.
This is the proper way to handle hardware Interrupts with FreeRTOS. The
more regular approach may/will lead to exceptions
* Added LEDC Fade exmaple
* Renamed LEDCFade example to LEDCSoftwareFade
Added valueMax parameter for ledcAnalogWrite
* Remove usage of LED_BUILTIN constant to solve CI errors