[proaudio] script to check for dups within the overlay

[Frieder Bürzele <evermind@xxxxxxxxxxxxx>]

Hi,

I wrote a script called ./check_for_dups. So as the name suggests it will
check for duplicates within the overlay

I've added it to the overlay, below is the link to the commit
(just for reference)

http://www.mail-archive.com/proaudio@xxxxxxxxxxxxxxxxxxx/msg02262.html

If you've have a problem or want a feature in it feel free to ask

Greetz Frieder