update readme

README.md

@@ -4,6 +4,8 @@ Spot trading docs [https://github.com/binance-exchange/binance-official-api-docs
 
 Futures trading docs [https://binance-docs.github.io/apidocs/futures/cn](https://binance-docs.github.io/apidocs/futures/cn)
 
+Delivery trading docs [https://binance-docs.github.io/apidocs/delivery/cn](https://binance-docs.github.io/apidocs/delivery/cn)
+
 Most of the interface is now complete, and the user can continue to extend it based on my design, working with me to improve it.
 
 [中文文档](https://github.com/zhouaini528/binance-php/blob/master/README_CN.md)

README_CN.md

@@ -1,8 +1,9 @@
 ### 建议您先阅读官方文档
 币币交易文档地址 [https://github.com/binance-exchange/binance-official-api-docs](https://github.com/binance-exchange/binance-official-api-docs)
 
-合约交易文档地址 [https://binance-docs.github.io/apidocs/futures/cn](https://binance-docs.github.io/apidocs/futures/cn)
+USDT合约交易文档地址 [https://binance-docs.github.io/apidocs/futures/cn](https://binance-docs.github.io/apidocs/futures/cn)
 
+币本位合约文档地址 [https://binance-docs.github.io/apidocs/delivery/cn](https://binance-docs.github.io/apidocs/delivery/cn)
 
 大部分的接口已经完成，使用者可以根据我的设计方案继续扩展，欢迎与我一起迭代它。