added readme links

packages/medusa-payment-paypal/README.md

@@ -1,11 +1,16 @@
 # medusa-payment-paypal
 
+Add PayPal as a Payment Provider.
+
+Learn more about how you can use this plugin in the [documentaion](https://docs.medusajs.com/add-plugins/paypal).
+
 ## Options
 
+```js
+{
+  sandbox: true, //default false
+  client_id: "CLIENT_ID", // REQUIRED
+  client_secret: "CLIENT_SECRET", // REQUIRED
+  auth_webhook_id: "WEBHOOK_ID" //REQUIRED for webhook to work
+}
 ```
-sandbox: [default: false],
-client_id: "CLIENT_ID", REQUIRED
-client_secret: "CLIENT_SECRET", REQUIRED
-auth_webhook_id: REQUIRED for webhook to work
-```
-