Better Documentation on how to install node modules using clever setup

[pilsy]

There is two ways to do this

1. If it's a module specific dependency you put it in the /backend/modules/$module/package.json
   you have to put the package inside the /backend/modules/$module/package.json and run clever setup
2. If it's a project specific one, you put it in /backend/package.json
   you can do npm install whatever --save or do the same as (1) by putting the dependency inside /backend/package.json and running clever setup