Installation instructions:
make shure you have the gpio command installed.
sudo su -
If not installed already run: apt-get install wiringpi
cp shutdown-button-pi.sh /usr/bin
chmod 755 /usr/bin/shutdown-button-pi.sh
cp shutdown-button-pi.service /usr/lib/systemd/system/
systemctl enable shutdown-button-pi.service


circuit diagram:

LED:
 pin 9 ---|<----[470 Ohm]-- pin 11 (gpio 17)
 
push button:
           /
 pin 9 ---/ ----[470 Ohm]-- pin 13 (gpio 27)
