Add README.
drwxr-xr-x - LUFA-111009
-rw-r--r-- 114 README.md
-rwxr-xr-x 625 arduino
drwxr-xr-x - dist
drwxr-xr-x - examples
drwxr-xr-x - hardware
drwxr-xr-x - lib
drwxr-xr-x - libraries
drwxr-xr-x - reference
-rw-r--r-- 61385 revisions.txt
drwxr-xr-x - tools