Simple library for using a 4x4-keypad with Arduino.
This library was published in 2009 by Angel Sancho angelitodeb@gmail.com and could be found here: http://arduino.cc/playground/Main/I2CPortExpanderAndKeypads
Changes where made by me regarding 'PIN MAPPING' and 'num_cols' to fit with my 4x4 keypads used with (DISPA or LocoIO-Editor)
Please read also the comment in i2ckeypad.cpp for more informations.