title: Composer: "Content-length mismatch" & "http://packagist.org could not be fully loaded..."
body: <p>When I try to create a new laravel project with "laravel new project"
  I got this  error: </p>
  
  <pre><code>Content-Length mismatch
  http://packagist.org could not be fully loaded, package information was loaded from the local cache and may be out of date
  </code></pre>
  
  <p>When I do "composer update" or "composer install doctrine/dbal", I got the error too.
  And my composer is too slow.</p>