Added ESP32 IR receive support (IRsend not implemented yet).

- disable a lot of defines not relevant to ESP32, set them to 1 (no-op)
- change default IR pin to 35 from 11
- changed serial speed to 115200 (9600 is too slow to keep up with IR input)
- irSend disables code that will not compile on ESP32. It won't work,
  but it won't break compilation either.

IRremote.cpp

@@ -18,7 +18,9 @@
 // Whynter A/C ARC-110WD added by Francesco Meschia
 //******************************************************************************
 
+#ifndef ESP32
 #include <avr/interrupt.h>
+#endif
 
 // Defining IR_GLOBAL here allows us to declare the instantiation of global variables
 #define IR_GLOBAL
@@ -120,7 +122,11 @@ int  MATCH_SPACE (int measured_ticks,  int desired_us)
 // As soon as first MARK arrives:
 //   Gap width is recorded; Ready is cleared; New logging starts
 //
+#ifdef ESP32
+void onTimer()
+#else
 ISR (TIMER_INTR_NAME)
+#endif
 {
 	TIMER_RESET;