README.MD is using property webcheckoutdetail in stead of webcheckoutdetailS #37
Description
See the follwing sections
Making a createCheckoutSession request
JSONObject payload = new JSONObject();
JSONObject webCheckoutDetail = new JSONObject();
webCheckoutDetail.put("checkoutReviewReturnUrl", "https://localhost/store/checkout_review");
payload.put("webCheckoutDetail", webCheckoutDetail);
### Making an updateCheckoutSession request
AmazonPayResponse response = null;
JSONObject payload = new JSONObject();
JSONObject updateWebCheckoutDetail = new JSONObject();
updateWebCheckoutDetail.put("checkoutResultReturnUrl", "https://localhost/store/checkout_return");
payload.put("webCheckoutDetail", updateWebCheckoutDetail);
These should be changed to
Making a createCheckoutSession request
JSONObject payload = new JSONObject();
JSONObject webCheckoutDetails = new JSONObject();
webCheckoutDetails.put("checkoutReviewReturnUrl", "https://localhost/store/checkout_review");
payload.put("webCheckoutDetails", webCheckoutDetails);
### Making an updateCheckoutSession request
```java
AmazonPayResponse response = null;
JSONObject payload = new JSONObject();
JSONObject updateWebCheckoutDetails = new JSONObject();
updateWebCheckoutDetails.put("checkoutResultReturnUrl", "https://localhost/store/checkout_return");
payload.put("webCheckoutDetails", updateWebCheckoutDetails);