title: NPM doesn't install module dependencies
body: <p>This is my <code>package.json</code> for the module that I'm including in the parent project:</p>
  
  <pre><code>{
    "version": "0.0.1",
    "name": "module-name",
    "dependencies": {
      "express": "3.3.4",
      "grunt": "0.4.1",
      "grunt-contrib-compass": "0.4.0",
      "grunt-contrib-copy": "0.4.1",
      "grunt-contrib-cssmin": "0.4.1",
      "grunt-contrib-jshint": "0.6.3",
      "grunt-contrib-requirejs": "0.4.1",
      "grunt-contrib-uglify": "0.2.2",
      "grunt-contrib-watch": "0.5.1",
      "grunt-express-server": "0.4.1",
      "grunt-karma": "0.4.5",
      "grunt-regex-replace": "0.2.5",
      "request": "2.25.0"
    },
    "scripts": {
      "postinstall": "grunt install"
    }
  }
  </code></pre>
  
  <p>One thing to note is that this module is contained in a private repo and I include it in the parent <code>package.json</code> like: <code>"module-name": "git+ssh://git@myserver:user/module-name.git"</code></p>