Added YNAB (#896)

README.md

@@ -323,6 +323,7 @@ API | Description | Auth | HTTPS | CORS |
 | [RoutingNumbers.info](https://www.routingnumbers.info/api/index.html) | ACH/NACHA Bank Routing Numbers | No | Yes | Unknown |
 | [Tradier](https://developer.tradier.com) | US equity/option market data (delayed, intraday, historical) | `OAuth` | Yes | Yes |
 | [VAT Rates](https://jsonvat.com/) | A collection of all VAT rates for EU countries | No | Yes | Unknown |
+| [YNAB](https://api.youneedabudget.com/) | Budgeting & Planning | `OAuth` | Yes | Yes | 
 
 ### Food & Drink
 API | Description | Auth | HTTPS | CORS |