Add worker loader to the examples

examples/worker.js

@@ -0,0 +1,35 @@
+/* eslint-disable no-console */
+
+import Map from '../src/ol/Map.js';
+import View from '../src/ol/View.js';
+import TileLayer from '../src/ol/layer/Tile.js';
+import OSM from '../src/ol/source/OSM.js';
+import {create as createVersionWorker} from '../src/ol/worker/version';
+
+
+const map = new Map({
+  layers: [
+    new TileLayer({
+      source: new OSM()
+    })
+  ],
+  target: 'map',
+  view: new View({
+    center: [0, 0],
+    zoom: 2
+  })
+});
+
+const worker = createVersionWorker();
+worker.addEventListener('error', function(error) {
+  console.error('worker error', error);
+});
+
+worker.addEventListener('message', function(event) {
+  console.log('message from worker:', event.data);
+});
+
+map.on('moveend', function(event) {
+  const state = event.frameState.viewState;
+  worker.postMessage({zoom: state.zoom, center: state.center});
+});