title: Enable php-intl in ISPConfig 3, Debian 8 and additional php 7.1 on server
body: <p>How to enable php-intl on php7.1 with Debian 8 + ISPConfig 3.x. It says, that it's installed on php7.1 but it is not enabled.
  If I run</p>
  
  <pre><code>./php --ri intl
  </code></pre>
  
  <p>I will get "Extension 'intl' not present."</p>