update node with node code example

Example 1: update nodejs

//First, clear the npm cache:
	npm cache clean -f

//Install n, Node’s version manager:
	npm install -g n
    
//With the n module installed, you can use it to:
	Install the latest stable version: n stable
	Install the latest release: n latest

Example 2: how to upgrade node.js

#linux
sudo npm install n -g
sudo n stable
#windows
#install the .msi from https://nodejs.org/en/download/