URL.openStream on directory URLs from the ShrinkWrapClassLoader throw an NPE

      // Make a new Archive with some content in a directory
      final String nestedResourceName = "nested/test";
      final Asset testAsset = new StringAsset("testContent");
      final GenericArchive archive = ShrinkWrap.create(GenericArchive.class).add(testAsset, nestedResourceName);
      
      // Make a CL to load the content
      final ClassLoader swCl = new ShrinkWrapClassLoader(archive);

      // Get the URL to the parent directory
      final URL nestedResourceUrl = swCl.getResource(nestedResourceName);
      final URL nestedResourceUpALevelUrl = new URL(nestedResourceUrl, "../");
      
      // openStream on the URL to the parent directory; should return null, not throw an exception
      final InputStream in = nestedResourceUpALevelUrl.openStream(); // << NPE