title: There is no extension able to load the configuration for "web_profiler"
body: <p>I'm quite new so Symfony2 and want to create a new environment called "dp". But for some reason I keep getting errors.</p>
  
  <pre><code>FileLoaderLoadException: Cannot import resource "/a/b/c/d/e/app/config/config_dev.yml" from "/a/b/c/d/e/app/config/config_dp.yml".
  InvalidArgumentException: There is no extension able to load the configuration for "web_profiler" (in /a/b/c/d/e/app/config/config_dev.yml). Looked for namespace "web_profiler", found "framework", "security", "twig", "monolog", "swiftmailer", "doctrine", "assetic", "sensio_framework_extra", "jms_security_extra", "smarty", "bela_meter", "bela_invoice", "bela_util"
  </code></pre>
  
  <p>I followed the Symfony2 <a href="http://symfony.com/doc/current/cookbook/configuration/environments.html" rel="noreferrer">documentation steps</a> 
  The contents of app/config/config_dp.yml is</p>
  
  <pre><code>imports:
  - { resource: config_dev.yml }
  </code></pre>
  
  <p>And web/app_dp.php contains:</p>
  
  <pre><code>$kernel = new AppKernel('dp', true);
  $kernel-&gt;loadClassCache();
  $kernel-&gt;handle(Request::createFromGlobals())-&gt;send();
  </code></pre>
  
  <p>How can I fix this? config_dev.yml environment works flawless.</p>