Add user to groups

[thijstriemstra]

I have an install.sh on the pi that adds the user to several groups, e.g.:

# setup permissions: add user to video, lpadmin, input and gpio groups
echo "Creating permissions..."
sudo groupadd -f -r gpio
sudo usermod -a -G gpio,lpadmin,video,input $(whoami)

Would be nice to have a setting that adds you to specified groups (and creates the group if it doesn't exist).

[FooDeas]

Good idea!