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/moveend.js

@@ -1,22 +1,21 @@
 import Map from '../src/ol/Map.js';
+import OSM from '../src/ol/source/OSM.js';
+import TileLayer from '../src/ol/layer/Tile.js';
 import View from '../src/ol/View.js';
 import {getBottomLeft, getTopRight} from '../src/ol/extent.js';
-import TileLayer from '../src/ol/layer/Tile.js';
 import {toLonLat} from '../src/ol/proj.js';
-import OSM from '../src/ol/source/OSM.js';
-
 
 const map = new Map({
   layers: [
     new TileLayer({
-      source: new OSM()
-    })
+      source: new OSM(),
+    }),
   ],
   target: 'map',
   view: new View({
     center: [0, 0],
-    zoom: 2
-  })
+    zoom: 2,
+  }),
 });
 
 function display(id, value) {
@@ -25,7 +24,7 @@ function display(id, value) {
 
 function wrapLon(value) {
   const worlds = Math.floor((value + 180) / 360);
-  return value - (worlds * 360);
+  return value - worlds * 360;
 }
 
 function onMoveEnd(evt) {