Update line numbers on existing icons

 map.html

@@ -26,6 +26,6 @@
<script src="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v5.3.0/build/ol.js" integrity="sha384-iQkGyyH4ioz3m+maM3s9MX1Oq67mACa4B9Z3ovUv3Sv37LJ96fx3WnZfLoiC3Wfl" crossorigin="anonymous"></script>
<script tyle="text/javascript" src="lang_pl.js?v6" id="lang_script"></script>
<script tyle="text/javascript" src="common.js?v6"></script>
<script tyle="text/javascript" src="map.js?v14"></script>
<script tyle="text/javascript" src="map.js?v15"></script>
</body>
</html>

 map.js

@@ -301,6 +301,7 @@
            } else {
                vehicle_feature.setProperties(vehicle);
                vehicle_feature.getStyle().getImage().setRotation(Math.PI * parseFloat(vehicle.heading ? vehicle.heading : 0) / 180.0);
                vehicle_feature.getStyle().getText().setText(vehicle.line);
            }
        }