title: Error during Travis-CI build with gradle and LibGDX
body: <p>I am trying to use Travis-CI with gradle to automatically build a LibGDX project. When <code>./gradle assemble</code> is run, it throws and error that is, 
  <code>Cannot find symbol 
  new LwjglApplication(new MainCoreClass(), config);</code> 
  It looks like a classpath problem but it isnt working.</p>