title: Ask for maven archetype properties with defaults
body: <p>I'm putting together a maven archetype that has a bunch of custom properties that are used to filter the various archetype resources. I have these specified with defaults in the archetype-metadata.xml e.g.</p>
  
  <pre><code>&lt;requiredProperties&gt;
    &lt;requiredProperty key="application-name"&gt;
      &lt;defaultValue&gt;Some Application&lt;/defaultValue&gt;
    &lt;/requiredProperty&gt;&gt;  
  &lt;/requiredProperties&gt;
  </code></pre>
  
  <p>However when I try to create a project with the archetype, it does not allow me to change these interactively. For instance, it asks for the version with default as follows</p>
  
  <pre><code>Define value for property 'version': 1.0-SNAPSHOT: 
  </code></pre>
  
  <p>allowing a version to be entered, but defaulting to 1.0-SNAPSHOT if nothing is entered. For my custom properties, it merely displays them prior to creating the new project </p>
  
  <pre><code>[INFO] Using property: application-name = Some Application
  </code></pre>
  
  <p>If I omit the default value from the archetype-metadata.xml then it will prompt me for a value, but there is no default.</p>
  
  <p>Is it possible to supply a default and still get prompted?</p>