Support non-AVR processors

Generalized interrupt handling for non-avr processors. Tested with Feather M0 and MKR1000

Version 1.1.0

Updated to use credit system (see http://forums.adafruit.com/viewtopic.php?f=53&t=70795&p=381409)

1.0.0 release for Arduino

Automated initial release for Arduino library system.