title: RuntimeException when I create a new Symfony Project
body: <p>good afternoon. I'm having trouble creating a new symfony project.
  When I enter the following command in the terminal:</p>
  
  <pre><code>symfony new mufasa
  </code></pre>
  
  <p>The terminal return to me the next message:</p>
  
  <blockquote>
    <p>[RuntimeException]<br>
      The selected version (3.3.12) cannot be installed because it does not exist<br>
      .<br>
      Execute the following command to install the latest stable Symfony release:<br>
      /usr/local/bin/symfony new mufasa                                            </p>
  </blockquote>
  
  <p>I have tried to update the symfony application using <code>symfony self-update</code> but is up to date:</p>
  
  <blockquote>
    <p>// Symfony Installer is already updated to the latest version (1.5.9).</p>
  </blockquote>
  
  <p>What can I do to solve this problem?</p>