message: docs: add core-js polyfills for StackBlitz support
  PR Close
diff: // import 'classlist.js'; // Run `npm install --save classlist.js`.
  /** IE10 and IE11 requires the following for the Reflect API. */
  -// import 'core-js/es6/reflect';
  +import 'core-js/es6/reflect';
  +import 'core-js/es7/reflect';
  /**
  * Web Animations `@angular/platform-browser/animations`
  