Removed 'new' from PinChangeInt library

As a consequence, only one pin is currently suppored.
AddPin will not really add a new pin, just replace the configuration
of the existing pin.

The motivation for this limitation is that 'new' costs a lot of
program memory.

libraries/PinChangeInt/PinChangeInt.h

@@ -234,6 +234,7 @@ protected:
 	volatile	uint8_t			portFallingPins;
 	volatile uint8_t		lastPinView;
 	PCintPin*	firstPin;
+	PCintPin	thePin;
 };
 
 #ifndef LIBCALL_PINCHANGEINT // LIBCALL_PINCHANGEINT ***********************************************
@@ -388,8 +389,9 @@ int8_t PCintPort::addPin(uint8_t arduinoPin, PCIntvoidFuncPtr userFunc, uint8_t
 		} while (true);
 	}
 
-	// Create pin p:  fill in the data.
-	PCintPin* p=new PCintPin;
+	// Create pin p:  fill in the data. NOTE: MySensors only support one pin due to size constraints
+	// TODO: Figure out a better way to solve this without relying on new/malloc
+	PCintPin* p = &thePin; //PCintPin* p=new PCintPin;
 	if (p == NULL) return(-1);
 	p->arduinoPin=arduinoPin;
 	p->mode = mode;