Use a newer version of Rasbpian (2013-09-10)

Also switch to pdf2htmlEX-0.9 and libpoppler37 (0.22.5-2)
Update README.md

add link to prebuild image
Fix #6 - Rename autorun from source key.
Merge branch 'master' of github.com:Rafiot/KittenGroomer
Make sure the led is always on.
remount the src key in RO without failing. Fix #1b5d4050b1c8eb2c321991197f629744db46aeb2
Fix #11

Play a sound while converting documents.
midi grooming tunes
Umount the 2 USB keys before shudown, fix #16.

Make sure the music/LED are still there as long as possible.
When the USB keys are umounted, the system is totally static and could
be plugged off.
Proper fix for #16.

/etc/mtab -> /proc/mounts to make sure umount knows the fs to work on.