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.

config/jsdoc/api/plugins/events.js

@@ -1,8 +1,7 @@
 const events = {};
 
 exports.handlers = {
-
-  newDoclet: function(e) {
+  newDoclet: function (e) {
     const doclet = e.doclet;
     if (doclet.kind !== 'event') {
       return;
@@ -15,7 +14,7 @@ exports.handlers = {
     events[cls].push(doclet.longname);
   },
 
-  parseComplete: function(e) {
+  parseComplete: function (e) {
     const doclets = e.doclets;
     for (let i = 0, ii = doclets.length - 1; i < ii; ++i) {
       const doclet = doclets[i];
@@ -34,6 +33,5 @@ exports.handlers = {
         }
       }
     }
-  }
-
+  },
 };