v2.0.0 Add support for ESP32S2 and update ESP-IDF to 4.4 (#4996)

This is very much still work in progress and much more will change before the final 2.0.0

Some APIs have changed. New libraries have been added. LittleFS included.

Co-authored-by: Seon Rozenblum <seonr@3sprockets.com>
Co-authored-by: Me No Dev <me-no-dev@users.noreply.github.com>
Co-authored-by: geeksville <kevinh@geeksville.com>
Co-authored-by: Mike Dunston <m_dunston@comcast.net>
Co-authored-by: Unexpected Maker <seon@unexpectedmaker.com>
Co-authored-by: Seon Rozenblum <seonr@3sprockets.com>
Co-authored-by: microDev <70126934+microDev1@users.noreply.github.com>
Co-authored-by: tobozo <tobozo@users.noreply.github.com>
Co-authored-by: bobobo1618 <bobobo1618@users.noreply.github.com>
Co-authored-by: lorol <lorolouis@gmail.com>
Co-authored-by: geeksville <kevinh@geeksville.com>
Co-authored-by: Limor "Ladyada" Fried <limor@ladyada.net>
Co-authored-by: Sweety <switi.mhaiske@espressif.com>
Co-authored-by: Loick MAHIEUX <loick111@gmail.com>
Co-authored-by: Larry Bernstone <lbernstone@gmail.com>
Co-authored-by: Valerii Koval <valeros@users.noreply.github.com>
Co-authored-by: 快乐的我531 <2302004040@qq.com>
Co-authored-by: chegewara <imperiaonline4@gmail.com>
Co-authored-by: Clemens Kirchgatterer <clemens@1541.org>
Co-authored-by: Aron Rubin <aronrubin@gmail.com>
Co-authored-by: Pete Lewis <601236+lewispg228@users.noreply.github.com>

libraries/BluetoothSerial/examples/SerialToSerialBT/SerialToSerialBT.ino

@@ -26,4 +26,4 @@ void loop() {
     Serial.write(SerialBT.read());
   }
   delay(20);
-}
+}

libraries/BluetoothSerial/examples/SerialToSerialBTM/SerialToSerialBTM.ino

@@ -14,7 +14,7 @@ String MACadd = "AA:BB:CC:11:22:33";
 uint8_t address[6]  = {0xAA, 0xBB, 0xCC, 0x11, 0x22, 0x33};
 //uint8_t address[6]  = {0x00, 0x1D, 0xA5, 0x02, 0xC3, 0x22};
 String name = "OBDII";
-char *pin = "1234"; //<- standard pin would be provided by default
+const char *pin = "1234"; //<- standard pin would be provided by default
 bool connected;
 
 void setup() {