Added KEY_PAUSE, KEY_PRINTSCREEN and KEY_SCROLL_LOCK missing keys. Added support to switch on/off a (external) LED through pins 14 and 15 to show Num-Lock and Scroll-Lock status .
Extra key (KEY_NON_US_BS) added to matrix to allow '<' and '>' key to be recognized by driver.
Don't forget to select 'Spanish' language in Arduino IDE (tools -> keyboard layout) if you are using a spanish layout keyboard!!