close with system.exit()

git-svn-id: svn+ssh://svn.internal.sanger.ac.uk/repos/svn/pathsoft/artemis/trunk@10595 ee4ac58c-ac51-4696-9907-e4b3aa274f04

uk/ac/sanger/artemis/circular/digest/CircularGenomeController.java

@@ -323,6 +323,7 @@ public class CircularGenomeController
   private void exitApp(JFrame f)
   {
     f.dispose();
+    System.exit(0);
   }
 
   /**