remove old node version ubuntu code example

Example 1: uninstall node js and npm ubuntu

sudo apt-get purge --auto-remove nodejs

Example 2: install node js using nvm ubuntu

curl -sL https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh -o install_nvm.sh

Example 3: install node js using nvm ubuntu

bash install_nvm.sh