message: improving ie11 compatibility
diff: */
  /** IE9, IE10 and IE11 requires all of the following polyfills. **/
  // import 'core-js/es6/symbol';
  -import "core-js/es6/object";
  +import 'core-js/es6/object';
  // import 'core-js/es6/function';
  // import 'core-js/es6/parse-int';
  // import 'core-js/es6/parse-float';
  // import 'core-js/es6/number';
  // import 'core-js/es6/math';
  -// import 'core-js/es6/string';
  +import 'core-js/es6/string';
  // import 'core-js/es6/date';
  -import "core-js/es6/array";
  +import 'core-js/es6/array';
  // import 'core-js/es6/regexp';
  // import 'core-js/es6/map';
  // import 'core-js/es6/weak-map';
  @@ -36,14 +36,14 @@ import "core-js/es6/array";
  /** IE10 and IE11 requires the following to support `@angular/animation`. */
  // import 'web-animations-js'; // Run `npm install --save web-animations-js`.
  /** Evergreen browsers require these. **/
  -import "core-js/es6/reflect";
  -import "core-js/es7/reflect";
  +import 'core-js/es6/reflect';
  +import 'core-js/es7/reflect';
  /** ALL Firefox browsers require the following to support `@angular/animation`. **/
  // import 'web-animations-js'; // Run `npm install --save web-animations-js`.
  /***************************************************************************************************
  * Zone JS is required by Angular itself.
  */
  -import "zone.js/dist/zone"; // Included with Angular CLI.
  +import 'zone.js/dist/zone'; // Included with Angular CLI.
  /***************************************************************************************************
  * APPLICATION IMPORTS
  */
  @@ -51,7 +51,7 @@ import "zone.js/dist/zone"; // Included with Angular CLI.
  * Date, currency, decimal and percent pipes.
  * Needed for: All but Chrome, Firefox, Edge, IE11 and Safari 10
  */
  -import "intl"; // Run `npm install --save intl`.
  +import 'intl'; // Run `npm install --save intl`.
  /**
  * Need to import at least one locale-data with intl.
  */
  