Add 'Run as a Kiosk' section to README

[mzac]

Added instructions for running the console as a kiosk on Raspberry Pi.

[peted-davis]

Thanks for the pull request. Can I check if this has been a specific issue you have been facing? What version of Raspberry Pi are you running on?

[mzac]

I'm running on a Raspberry Pi 3 Model B with the official 7" DSI touchscreen, Raspbian Bullseye 32-bit.

On boot, the LXDE panel and desktop loaded behind the console window, and the console itself came up maximized rather than fullscreen — so the LXDE top bar was visible and I had to click the taskbar entry once or twice to get it to cover the whole screen.

Thse are the two changes that are what fixed it for me:

1. Replacing the LXDE autostart with just the xset screen-blanking lines, so no panel/pcmanfm comes up.
2. Setting fullscreen = auto and borderless = 1 in ~/.kivy/config.ini so the window goes truly fullscreen without window decorations.