add changelog for v2.3.1

Author: roseduan

CHANGELOG.md

@@ -1,3 +1,12 @@
+# Release 2.3.1(2023-08-21)
+## 🚀 New Features
+* Support key expire
+  * You can call `PutWithTTL` to set the expire time for a key.
+
+## 🎠 Community
+* Thanks to @weijiew 
+    * Add more BTree functions #264
+
 # Release 2.3.0(2023-08-18)
 ## 🚀 New Features
 * use BTree as the default memory data structure.

README-CN.md

@@ -80,6 +80,11 @@ RoseDB 存储数据的文件使用预写日志（Write Ahead Log），这些日
     RoseDB 支持 Watch 功能，DB 中的 key 发生变化时你可以得到一个事件通知。
 </details>
 
+<details>
+    <summary><b>支持 Key 的过期时间</b></summary>
+    RoseDB 支持为 key 设置过期时间，过期后 key 将被自动删除。
+</details>
+
 ### 缺点
 
 <details>

README.md

@@ -81,6 +81,11 @@ RoseDB log files are using the WAL(Write Ahead Log) as backend, which are append
 	RoseDB supports key watch, you can get the notification if keys changed in db.
 </details>
 
+<details>
+    <summary><b>Support key expire</b></summary>
+	RoseDB supports key expire, you can set the expire time for keys.
+</details>
+
 ### Weaknesses
 
 <details>