docs:add CHANGELOG.md.

CHANGELOG.md

@@ -0,0 +1,13 @@
+# Change Log
+---
+
+- [the server address only support one ip](https://github.com/Tencent/spring-cloud-tencent/pull/36)
+- [feature: get service list by given namespace](https://github.com/Tencent/spring-cloud-tencent/pull/38)
+- [feat:Support multi-discovery server.](https://github.com/Tencent/spring-cloud-tencent/pull/42)
+- [fix:fix [Deserialization of Untrusted Data in logback]](https://github.com/Tencent/spring-cloud-tencent/pull/44/files)
+- [feat:support customize registered ip address.](https://github.com/Tencent/spring-cloud-tencent/pull/47)
+- [https://github.com/Tencent/spring-cloud-tencent/pull/51](https://github.com/Tencent/spring-cloud-tencent/pull/51)
+- [fix:fix import default log implement error](https://github.com/Tencent/spring-cloud-tencent/pull/53)
+- [send heartbeat if healthcheck url not configured](https://github.com/Tencent/spring-cloud-tencent/pull/54)
+- [feat:optimize project structure and checkstyle](https://github.com/Tencent/spring-cloud-tencent/pull/56)
+- [feat:divide storage and transfer of metadata.](https://github.com/Tencent/spring-cloud-tencent/pull/63)

CONTRIBUTING.md

@@ -23,4 +23,5 @@ Please confirm before completing a PR:
 3. Please add License and Copyright declarations in the newly created file.
 4. Ensure a consistent code style.
 5. Do adequate testing.
-6. Then, you can submit your code to the dev branch.
+6. Add this pull request info to [CHANGELOG](./CHANGELOG.md).
+7. Then, you can submit your code to the dev branch.