Make code prettier

This updates ESLint and our shared eslint-config-openlayers to use Prettier.  Most formatting changes were automatically applied with this:

    npm run lint -- --fix

A few manual changes were required:

 * In `examples/offscreen-canvas.js`, the `//eslint-disable-line` comment needed to be moved to the appropriate line to disable the error about the `'worker-loader!./offscreen-canvas.worker.js'` import.
 * In `examples/webpack/exapmle-builder.js`, spaces could not be added after a couple `function`s for some reason.  While editing this, I reworked `ExampleBuilder` to be a class.
 * In `src/ol/format/WMSGetFeatureInfo.js`, the `// @ts-ignore` comment needed to be moved down one line so it applied to the `parsersNS` argument.

examples/here-maps.js

@@ -1,6 +1,6 @@
 import Map from '../src/ol/Map.js';
-import View from '../src/ol/View.js';
 import TileLayer from '../src/ol/layer/Tile.js';
+import View from '../src/ol/View.js';
 import XYZ from '../src/ol/source/XYZ.js';
 
 const appId = 'kDm0Jq1K4Ak7Bwtn8uvk';
@@ -11,60 +11,66 @@ const hereLayers = [
     type: 'maptile',
     scheme: 'normal.day',
     app_id: appId,
-    app_code: appCode
+    app_code: appCode,
   },
   {
     base: 'base',
     type: 'maptile',
     scheme: 'normal.day.transit',
     app_id: appId,
-    app_code: appCode
+    app_code: appCode,
   },
   {
     base: 'base',
     type: 'maptile',
     scheme: 'pedestrian.day',
     app_id: appId,
-    app_code: appCode
+    app_code: appCode,
   },
   {
     base: 'aerial',
     type: 'maptile',
     scheme: 'terrain.day',
     app_id: appId,
-    app_code: appCode
+    app_code: appCode,
   },
   {
     base: 'aerial',
     type: 'maptile',
     scheme: 'satellite.day',
     app_id: appId,
-    app_code: appCode
+    app_code: appCode,
   },
   {
     base: 'aerial',
     type: 'maptile',
     scheme: 'hybrid.day',
     app_id: appId,
-    app_code: appCode
-  }
+    app_code: appCode,
+  },
 ];
-const urlTpl = 'https://{1-4}.{base}.maps.cit.api.here.com' +
+const urlTpl =
+  'https://{1-4}.{base}.maps.cit.api.here.com' +
   '/{type}/2.1/maptile/newest/{scheme}/{z}/{x}/{y}/256/png' +
   '?app_id={app_id}&app_code={app_code}';
 const layers = [];
 let i, ii;
 for (i = 0, ii = hereLayers.length; i < ii; ++i) {
   const layerDesc = hereLayers[i];
-  layers.push(new TileLayer({
-    visible: false,
-    preload: Infinity,
-    source: new XYZ({
-      url: createUrl(urlTpl, layerDesc),
-      attributions: 'Map Tiles &copy; ' + new Date().getFullYear() + ' ' +
-        '<a href="http://developer.here.com">HERE</a>'
+  layers.push(
+    new TileLayer({
+      visible: false,
+      preload: Infinity,
+      source: new XYZ({
+        url: createUrl(urlTpl, layerDesc),
+        attributions:
+          'Map Tiles &copy; ' +
+          new Date().getFullYear() +
+          ' ' +
+          '<a href="http://developer.here.com">HERE</a>',
+      }),
     })
-  }));
+  );
 }
 
 const map = new Map({
@@ -72,8 +78,8 @@ const map = new Map({
   target: 'map',
   view: new View({
     center: [921371.9389, 6358337.7609],
-    zoom: 10
-  })
+    zoom: 10,
+  }),
 });
 
 function createUrl(tpl, layerDesc) {