title: Opencart vqmod error Cannot redeclare modification()
body: <p>I have opencart Version 2.0.3.1 and installed vqmod-2.5.1-opencart.
  I was installing a extension by extension installer by upload the zip file of extension.</p>
  
  <p>I got the error: </p>
  
  <blockquote>
    <p>"Fatal error: Cannot redeclare modification() (previously declared in
    /home/username/public_html/mydomain.com/vqmod/vqcache/vq2-system_startup.php:49)
    in /home/username/public_html/mydomain.com/system/startup.php on line
    65"</p>
  </blockquote>
  
  <p>And I couldn't finish my installer. Anyone had this problem and fixed it?</p>