title: npm config list - multiple config
body: <p>i have created a project using npm init and i created a .npmrc file with some config. when i check the npm config list i am getting project config and userconfig. </p>
  
  <p>do i need to remove the userconfig , but i am not able to edit the file.</p>
  
  <p>i am not understanding why we need the .npmrc file , when you hit a command npm install express , all the config is done in the npm config file ?</p>
  
  <p>how to edit the .npmrc global file in ubuntu ?</p>
  
  <p>do we need to remove the userconfig if we need to use project config ? or its something like which ever comes it takes that</p>