Support for ISO/JIS keys on ADB(Issue#22)

- ISO/JIS specific keys support.(Not tested :)
- Learned how to convert ADB into HID code from:
  http://www.opensource.apple.com/source/IOHIDFamily/IOHIDFamily-421.18.3/IOHIDFamily/Cosmo_USB2ADB.c
- Left of 1 key generates 0x0A(ADB scan code) on German layout AEKII.
Teensy 2.0 specific changes