Intel NUC / Ubuntu 14.04 Rise Vision info display needs to turn off as soon as power button pressed

We've got an Intel NUC, one of the DN2820FYK kits - except its really a DN2830 - we use with the Rise Vision platform to run an information display in a reception area. Very nice bit of kit, boots in no time with Ubuntu 14.04 and a Kingston V300 SSD.

(As an aside, we did test with a Raspberry Pi, but it was just too slow. We've got 4 dynamic elements on the screen plus time, date, logo, weather and unfortunately the Pi just kept getting stuck with 100% cpu)

However we need it to shutdown right away if staff press the power button, not prompt with the confirmation dialog. Thanks to maketecheasier we found the following terminal command to sort that:

gsettings set com.canonical.indicator.session suppress-logout-restart-shutdown true

Press the NUC power button and it will be down in under 5s !