Show something not nothing if the window is an unknown type (Window status plugin)

git-svn-id: http://svn.dmdirc.com/trunk@2863 00569f92-eb28-0410-84fd-f71c24880f

src/com/dmdirc/addons/windowstatus/WindowStatusPlugin.java

@@ -201,6 +201,8 @@ public final class WindowStatusPlugin extends Plugin implements ActionListener,
 					}
 				}
 			}
+		} else {
+			textString.append("???");
 		}
 		label.setText(textString.toString());
 	}