GUI: added close() call to Dialog::runModal()

This should prevent a small leak in the GuiManager when adding the dialog to the stack. Check for any regressions.

svn-id: r53747

gui/dialog.cpp

@@ -76,6 +76,8 @@ int Dialog::runModal() {
 	// Start processing events
 	g_gui.runLoop();
 
+	close();	// to prevent resource leak in GUI manager
+	
 	// Return the result code
 	return _result;
 }