title: android lint unused resources from library module are used in app
body: <p>My app is split up in a main app and different library modules. 
  When I run </p>
  
  <pre><code>./gradlew lint 
  </code></pre>
  
  <p>each module is checked independently and for each module a lint.xml file is generated. In the lint.xml files there were tons of unused resources warnings, but that resources are used in the main app.
  How can I configure lint to check globally in the app if a resources is used or not?</p>
  
  <p>Thanks :)</p>