Update gui-qt.py example file so it works with the new Qt GUI support.

docs/examples/lib/gui-qt.py

@@ -35,6 +35,9 b" if __name__ == '__main__':"
     sw.show()
 
     try:
-        from IPython import enable_qt4; enable_qt4(app)
+        from IPython.lib.inputhook import enable_qt4
+        enable_qt4()
+        from IPython.lib.guisupport import start_event_loop_qt4
+        start_event_loop_qt4(app)
     except ImportError:
         app.exec_()