title: Maven filter resources and adding project version
body: <p>This is an easy filter approach to write the project version into a file.</p>
  
  <pre><code>&lt;build&gt;
   &lt;resources&gt;
    &lt;resource&gt;
      &lt;directory&gt;src/main/webapp&lt;/directory&gt;
      &lt;includes&gt;
        &lt;include&gt;**/*.version&lt;/include&gt;
      &lt;/includes&gt;
      &lt;filtering&gt;true&lt;/filtering&gt;
    &lt;/resource&gt;
   &lt;/resources&gt;
  &lt;/build&gt;
  </code></pre>
  
  <p>This is the project structure (left out the unintresting parts)</p>
  
  <pre><code>├───src
  │   └───main
  │       ├───java
  │       │   └─── [...]
  │       └───webapp
  │           ├───META-INF
  │           └───WEB-INF
  │               ├───cfg
  │               └───portal.version
  └─── pom.xml
  </code></pre>
  
  <p>The content of <code>portal.version</code></p>
  
  <pre><code>${project.version}
  </code></pre>
  
  <p>This should be replaced with the artifact version of the <code>pom.xml</code>, but unfortunately nothing happens. Whats wrong? Thank you in advance</p>