title: npm install won't install devDependencies
body: <p>On windows for some reason when I run <code>npm install</code> it won't install <strong>devDependencies</strong>. AFAIK it should. If I run <code>npm install --dev</code> <strong>devDependencies</strong> are installed. I don't understand why <code>npm install</code> doesn't install <strong>devDependencies</strong> too, but installs only dependencies. What could be the reason? How can I fix it?</p>
  
  <p>Maybe something is wrong with my <em>package.json</em>? It is listed below if it may be helpful:</p>
  
  <pre><code>{
    "name": "try-brunch",
    "version": "0.1.0",
    "private": "true",
    "devDependencies": {
      "brunch": "^2.0.4",
      "cssnano-brunch": "^1.1.5",
      "javascript-brunch": "^1.8.0",
      "sass-brunch": "^1.9.2",
      "uglify-js-brunch": "^1.7.8"
    },
    "dependencies": {
      "jquery": "^2.1.4"
    }
  }
  </code></pre>