title: Programmatic way of checking if npm packages in package.json are used in project?
body: <p>If I have a project written in node, with a package.json and a number of directories/sub-directories, is there any way of checking that all modules listed in package.json are actually being used in the project? </p>
  
  <p>Take the scenario of multiple people committing to the project, adding npm packages here and there, adopting new ones as the project progresses, but never removing the old ones. </p>