Update readme with instructions for commonJS and ES modules

README.md

@@ -22,10 +22,16 @@ yarn add @incognia/api
 
 Require the package:
 
+CommonJS modules:
 ```js
 const { IncogniaApi } = require('@incognia/api')
 ```
 
+Or ES modules:
+```js
+import { IncogniaApi } from "@incognia/api";
+```
+
 Instantiate with your clientId and clientSecret:
 
 ```js