Raspberry Pi/Rename user pi

change user "pi" to "marcluer":

passwd
sudo passwd               # activate root access
sed -i '/^#PermitRootLogin.*/a PermitRootLogin yes' /etc/ssh/sshd_config

reboot
ssh root@...

usermod -l marcluer -d /home/marcluer -m pi
groupmod -n marcluer pi
sed -i 's/pi/marcluer/g' /etc/sudoers.d/010_pi-nopasswd
sed -i 's/PermitRootLogin yes/#PermitRootLogin yes/g' /etc/ssh/sshd_config
sudo passwd -l root       # deactivate root access

reboot
ssh marcluer@...