Add: another go-to-location button to the sign window.

src/widgets/sign_widget.h

@@ -24,6 +24,7 @@ enum SignListWidgets {
 /** Widgets of the #SignWindow class. */
 enum QueryEditSignWidgets {
 	WID_QES_CAPTION,  ///< Caption of the window.
+	WID_QES_LOCATION, ///< Scroll to sign location.
 	WID_QES_TEXT,     ///< Text of the query.
 	WID_QES_OK,       ///< OK button.
 	WID_QES_CANCEL,   ///< Cancel button.