title: Add multiple library in composer.json
body: <p>Actually I have tried this but it doesn't work. I'd like to preserve authors and descriptions. Of course I can do without. However I would like to know how to make this possible.</p>
  
  <pre><code>{
      "name": "masterexploder/PHPThumb",
      "type": "library",
      "description": "A library for manipulating images in PHP.",
      "homepage": "https://github.com/masterexploder/PHPThumb",
      "keywords": ["image", "resize", "rotate"],
      "require": {
              "php": "&gt;=5.3.0",
              "symfony/filesystem": "2.2.*"
      },
      "authors": [
          {
              "name": "Ian Selby",
              "email": "ian@gxdlabs.com"
          }
      ],
      "autoload": {
          "psr-0": {
              "PHPThumb": "src",
              "PHPThumb\\Tests": "tests"
          }
      }
  
  },
  {
      "name": "alexshelkov/simpleacl",
      "type": "library",
      "description": "Simple Access Control List (ACL) for PHP.",
      "keywords": ["ACL", "authorization", "permission"],
      "homepage": "https://github.com/alexshelkov/SimpleAcl",
      "require": {
          "php": "&gt;=5.3.0"
      },
      "authors": [
          {
              "name": "Alex Shelkovskiy",
              "email": "alexshelkov@gmail.com",
              "role": "Developper"
          }
      ],
      "autoload": {
          "psr-0": {
              "SimpleAcl": "SimpleAcl/"
          }
      }
  }
  </code></pre>