Added ESP32-S2 support

Update compatibility with ESP32

Version 2.2.2

- Added compatibility with the ESP32 Arduino framework
- Added full featured AnalogWrite methods for ESP32 to control up to 9 PWM and 2 DAC signals.

New Version 2.2.1

- Even faster AutoTune function
- AutoTune  now determines the  controllability of the process
- Added AMIGO_PID tuning rule
- Added `GetTd()` function to display dead time

QuickPID 2.2.0

Includes enhanced AutoTune,
8 tuning rules to choose from
and GetKu() and GetTu() display functions.

New Version with AutoTune

Added MIT license, POn default = 1

QuickPID 2.0.4

Added QuickPID_AdaptiveTunings.ino, QuickPID_Basic.ino, QuickPID_PonM.ino and QuickPID_RelayOutput.ino to the examples folder. Note thatQuickPID_RelayOutput.ino has the added feature of minWindow setting that sets the minimum on time for the relay.

QuickPID 2.0.3