title: How to install only "devDependencies" using npm
body: <p>I am trying to install ONLY the "devDependencies" listed in my package.json file. But none of the following commands work as I expect. All of the following commands install the production dependencies also which I do not want.</p>
  
  <pre><code>npm install --dev
  npm install --only=dev
  npm install --only-dev
  </code></pre>
  
  <p>I cannot think of any more ways of telling the npm to install the devDependencies alone. :( </p>