Improve Typescript support

Author: vallpaper

README.md

@@ -15,7 +15,7 @@ The library is [UMD](https://github.com/umdjs/umd) compatible.
 You can download [recombee-api-client.min.js](./dist/recombee-api-client.min.js) and host it at your site, or use a CDN such as [jsDelivr](https://www.jsdelivr.com/) CDN:
 
 ```js
-<script src="https://cdn.jsdelivr.net/gh/recombee/js-api-client@4.1.2/dist/recombee-api-client.min.js"></script>
+<script src="https://cdn.jsdelivr.net/gh/recombee/js-api-client@4.1.3/dist/recombee-api-client.min.js"></script>
 ```
 
 ### npm
@@ -189,7 +189,7 @@ Let's assume we want to show recommendations at product page of pants `product-2
         </div>
     </div>
 
-    <script src="https://cdn.jsdelivr.net/gh/recombee/js-api-client@4.1.2/dist/recombee-api-client.min.js"></script>
+    <script src="https://cdn.jsdelivr.net/gh/recombee/js-api-client@4.1.3/dist/recombee-api-client.min.js"></script>
 
     <script type="text/javascript">
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "recombee-js-api-client",
-  "version": "4.1.2",
+  "version": "4.1.3",
   "description": "Client-side js library for easy use of the Recombee recommendation API",
   "browser": "./src/index.js",
   "types": "src/index.d.ts",