Aeon Nox power button

I’m configuring the Aeon Nox skin to my personal preferences and I’m trying to make a power button like in the example below, so I can remove the power menu/submenu and save some space on the main menu.

watch gallery

I found a topic in the kodi wiki called button control, but not a lot of information on how to install this. I googled for a tutorial, but can’t find any. Can someone give me a little push in the right direction?