workaround for Java 1.7 where javax.swing.JComboBox<E> is generic;

--- a/src/Tools/jEdit/src/isabelle_options.scala	Sun Aug 07 23:05:50 2011 +0200
+++ b/src/Tools/jEdit/src/isabelle_options.scala	Sun Aug 07 23:08:07 2011 +0200
@@ -27,7 +27,8 @@
 
   override def _init()
   {
-    addComponent(Isabelle.Property("logic.title"), logic_selector.peer)
+    addComponent(Isabelle.Property("logic.title"),
+      logic_selector.peer.asInstanceOf[java.awt.Component])
 
     addComponent(Isabelle.Property("auto-start.title"), auto_start.peer)
     auto_start.selected = Isabelle.Boolean_Property("auto-start")