title: Tomcat 8 - Include external files
body: <p>I'm running Tomcat 8 on Linux and there I have a folder</p>
  
  <pre><code>/opt/files
  </code></pre>
  
  <p>where tomcat and other applications should save and access files. 
  However, I don't know how to set this up in Tomcat to make use of these files</p>