title: How to enable compass-import-once in maven
body: <p>According to <a href="http://www.geodienstencentrum.nl/sass-maven-plugin/dependencies.html" rel="nofollow">this</a>, the sass-maven-plugin includes <a href="https://github.com/chriseppstein/compass/tree/master/import-once" rel="nofollow">compass-import-once</a>.</p>
  
  <p>I would like to know how I can enable this feature in my maven project. Relevant excerpt of my pom.xml:</p>
  
  <pre><code>&lt;plugin&gt;
       &lt;groupId&gt;nl.geodienstencentrum.maven&lt;/groupId&gt;
       &lt;artifactId&gt;sass-maven-plugin&lt;/artifactId&gt;
       &lt;version&gt;2.0-RC2&lt;/version&gt;
       &lt;configuration&gt;
           ...
           &lt;useCompass&gt;true&lt;/useCompass&gt;
           &lt;gems&gt;
               &lt;gem&gt;compass-import-once&lt;/gem&gt;
           &lt;/gems&gt;
       &lt;/configuration&gt;
   &lt;/plugin&gt;
  </code></pre>
  
  <p>When I run <code>mvn sass:watch</code>, in the output, the following line is included: "Running with Compass enabled". However, in my <code>.scss</code> file,</p>
  
  <pre><code>@import "foo"
  @import "foo"
  </code></pre>
  
  <p>still causes all the elements in "foo" to be included twice in the compiled css.</p>