Merge pull request arduino-libraries#171 from arduino-libraries/karlsoderby/add-images

Added pinout

Author: karlsoderby

docs/arduino_mega_ethernet_pins.png

@@ -4,6 +4,10 @@ This library is designed to work with the Arduino Ethernet Shield, Arduino Ether
 
 The Arduino board communicates with the shield using the SPI bus. This is on digital pins 11, 12, and 13 on the Uno and pins 50, 51, and 52 on the Mega. On both boards, pin 10 is used as SS. On the Mega, the hardware SS pin, 53, is not used to select the Ethernet controller chip, but it must be kept as an output or the SPI interface won't work.
 
+![Arduino UNO Pin map.](./arduino_uno_ethernet_pins.png)
+
+![Arduino MEGA Pin map.](./arduino_mega_ethernet_pins.png)
+
 ```
 To use this library
 #include <SPI.h>