title: jib-maven-plugin - How to set folder permission
body: <p>I'm trying to build docker image using <strong>jib-maven-plugin</strong>, I want to set permission for specific folder.
  If I am using docker file, the configuration will look below :</p>
  <pre><code>FROM xxxxxxxx.com/sandbox/gui-server:1.0.0-SNAPSHOT
  USER root
  RUN chmod 755 /home/www
  USER www
  </code></pre>
  <p>Now how do I implement this using jib-maven-plugin? I believe somewhere in <strong>pom.xml</strong> in <strong>jib-maven-plugin</strong></p>
  <pre><code>&lt;container&gt;
     &lt;mainClass&gt;${mainClass}&lt;/mainClass&gt;
        ...
          ...
        &lt;user&gt;www&lt;/user&gt;
  &lt;/container&gt;
  </code></pre>