Added support for Arduino Leonardo

The Teensy 2.0 is no longer the default, as both the Leonardo and
Teensy 2.0 is using the ATmega32u4.
To use the Teensy 2.0 you have to uncomment "#define BOARD_TEENSY" in
avrpins.h

avrpins.h

@@ -23,6 +23,8 @@ e-mail   :  support@circuitsathome.com
 /* Uncomment the following if you have Arduino Mega ADK board with MAX3421e built-in */
 //#define BOARD_MEGA_ADK
 
+/* Uncomment the following if you are using a Teensy 2.0 */
+//#define BOARD_TEENSY
 
 #include <avr/io.h>
 
@@ -501,7 +503,47 @@ template<typename Tp_pin, typename Tc_bit>
 
 #endif // "Classic" Arduino pin numbers
 
-#if defined(__AVR_ATmega32U4__)
+#if !defined(BOARD_TEENSY) && defined(__AVR_ATmega32U4__) 
+// Arduino Leonardo pin numbers
+
+#define P0  Pd2 // D0 - PD2
+#define P1  Pd3 // D1 - PD3
+#define P2  Pd1 // D2 - PD1
+#define P3  Pd0 // D3 - PD0
+#define P4  Pd4 // D4 - PD4
+#define P5  Pc6 // D5 - PC6
+#define P6  Pd7 // D6 - PD7
+#define P7  Pe6 // D7 - PE6
+
+#define P8  Pb4 // D8 - PB4
+#define P9  Pb5 // D9 - PB5
+#define P10 Pb6 // D10 - PB6
+#define P11 Pb7 // D11 - PB7
+#define P12 Pd6 // D12 - PD6
+#define P13 Pc7 // D13 - PC7
+
+#define P14 Pb3 // D14 - MISO - PB3
+#define P15 Pb1 // D15 - SCK - PB1
+#define P16 Pb2 // D16 - MOSI - PB2
+#define P17 Pb0 // D17 - SS - PB0
+
+#define P18 Pf7 // D18 - A0 - PF7
+#define P19 Pf6 // D19 - A1 - PF6
+#define P20 Pf5 // D20 - A2 - PF5
+#define P21 Pf4 // D21 - A3 - PF4
+#define P22 Pf1 // D22 - A4 - PF1
+#define P23 Pf0 // D23 - A5 - PF0
+
+#define P24 Pd4 // D24 / D4 - A6 - PD4
+#define P25 Pd7 // D25 / D6 - A7 - PD7
+#define P26 Pb4 // D26 / D8 - A8 - PB4
+#define P27 Pb5 // D27 / D9 - A9 - PB5
+#define P28 Pb6 // D28 / D10 - A10 - PB6
+#define P29 Pd6 // D29 / D12 - A11 - PD6
+
+#endif // Arduino Leonardo pin numbers
+
+#if defined(BOARD_TEENSY) && defined(__AVR_ATmega32U4__) 
 // Teensy 2.0 pin numbers
 // http://www.pjrc.com/teensy/pinout.html
 #define P0  Pb0