End Stop to Power off printer

I use Octoprint to make my Rapide Lite 200 wireless. But i need a way to shutdown my printer when not at home.

I created a End Stop holder and bought a End Stop switch and placed it to the side of my Rapide Lite.

I bought this: http://bit.ly/145eNPy
Its a microswitch connected through COM and NC. This means, that when the switch is made it cuts the power through the circuit. When i run my X-axis to the max distance of the print bed (~195 mm from the home position) the switches wheel hits the side of the platform on which the printbed is placed - and the switch cuts the power to the printer.

Since my printer uses Marlin, i havent found a way to use any gcode commands to shut it down. I saw that you can use the M81-command to shut it down, but that didnt work on my printer - so i had to create this.

EDIT: You can do this by wiring the RAMPS board. I didnt know this at the time of this creation - but heres a link for you:
https://github.com/foosel/OctoPrint/wiki/Control