title: Where to place webpack.config.js in create-react-app project
body: <p>I have been instructed to put some instructions inside the webpack.config.js file.
  However in my create-react-app project I cannot find that file.
  Currently the available answer on StackOverFlow requires ejecting the project which I think will break my project.
  Is it possible to use webpack.config.js inside a create-react-app project without ejecting?
  Where is the webpack.config.js file? or where should I put it?</p>