Latest Python-Telegram-Bot API update

[janvangent]

PTB (Python Telegram Bot) has gone through quite some changes recently.
In December 2022, PTB went from version 13.15 to 20.X, and there are quite a lot of changes so it appears.
Some of these seem to impact the familiekiosk... I currently don't have the time to dig into it, and try to fix the code to make it work for 20.X, so I took the quick & dirty route instead: downgraded to 13.15 by using the following command:
sudo pip install python-telegram-bot==13.15

In case someone would find the time to work on an update of the familiekiosk code, so it can deal with 20.X, here is a transition guide:
https://github.com/python-telegram-bot/python-telegram-bot/wiki/Transition-guide-to-Version-20.0