title: Composer won't install "require-dev" packages
body: <p>I'm trying to do some development with Laravel, and for some reason I can't get it to install any of the packages listed in the <code>require-dev</code> section in any of the dependencies' <code>composer.json</code> files.  AFAIK, dev dependencies are supposed to be installed by default.  I've tried it with and without the <code>--dev</code> flag on <code>composer install</code>.  I've also tried removing the contents of <code>vendors/</code> and deleting <code>composer.lock</code> and <code>~/.composer</code> and reinstalling all the dependencies from scratch, but still no luck.  I've also tried various iterations of the <code>composer update</code> command.</p>
  
  <p>For example, in <code>vendor/laravel/framework/composer.json</code>, it lists these:</p>
  
  <pre><code>"require-dev": {
      "aws/aws-sdk-php": "2.4.*",
      "iron-io/iron_mq": "1.4.*",
      "pda/pheanstalk": "2.1.*",
      "mockery/mockery": "0.8.0",
      "phpunit/phpunit": "3.7.*"
  },
  </code></pre>
  
  <p>None of these are getting installed.  Any ideas what am I missing?  Here's my main <code>composer.json</code> file, FWIW.</p>
  
  <pre><code>{
  "name": "laravel/laravel",
  "description": "The Laravel Framework.",
  "keywords": ["framework", "laravel"],
  "license": "MIT",
  "require": {
      "laravel/framework": "4.0.*",
      "rncryptor/rncryptor-php": "1.*"
  },
  "autoload": {
      "classmap": [
          "app/commands",
          "app/controllers",
          "app/models",
          "app/libraries",
          "app/database/migrations",
          "app/database/seeds",
          "app/tests/TestCase.php"
      ]
  },
  "scripts": {
      "post-install-cmd": [
          "php artisan optimize"
      ],
      "pre-update-cmd": [
          "php artisan clear-compiled"
      ],
      "post-update-cmd": [
          "php artisan optimize"
      ],
      "post-create-project-cmd": [
          "php artisan key:generate"
      ]
  },
  "config": {
      "preferred-install": "dist"
  },
  "minimum-stability": "dev"
  }
  </code></pre>
  
  <p>I ran <code>composer self-update</code>, so it should be the latest version.  Running <code>composer --version</code> shows this:</p>
  
  <pre><code>Composer version b20021cc6aa113069e4223b78d0074a1fc7dd4e8 2014-01-14 16:22:09
  </code></pre>