feat: add ES module bundle

Author: tsvetomir

package.json

@@ -6,10 +6,12 @@
     "type": "git",
     "url": "https://github.com/telerik/kendo-intl.git"
   },
-  "main": "dist/npm/js/main.js",
-  "typings": "dist/npm/js/main",
+  "main": "dist/npm/main.js",
+  "module": "dist/es/main.js",
+  "jsnext:main": "dist/es/main.js",
+  "typings": "dist/es/main",
   "scripts": {
-    "build-package": "gulp build-npm-package",
+    "build-package": "gulp build-rollup-package",
     "test": "gulp test",
     "lint": "gulp lint",
     "semantic-release": "semantic-release pre && npm publish && semantic-release post"

src/errors.js

@@ -3,9 +3,6 @@ import errorDetails from './error-details';
 const formatRegExp = /\{(\d+)}?\}/g;
 
 class IntlError {
-    name = "";
-    message = "";
-
     constructor({ name, message }) {
         if (!name || !message) {
             throw new Error("{ name: string, message: string } object is required!");