add joinus (#350)

README.md

@@ -33,6 +33,13 @@ PaddleClas is a toolset for image classification tasks prepared for the industry
 - Support Linux, Windows, macOS and other systems.
 
 
+## Community
+
+* Scan the QR code below with your Wechat, you can access to official technical exchange group. Look forward to your participation.
+
+![](docs/images/joinus.png)
+
+
 ## Tutorials
 
 - [Installation](./docs/en/tutorials/install_en.md)

README_cn.md

@@ -36,6 +36,13 @@
 - 可运行于Linux、Windows、MacOS等多种系统。
 
 
+## 欢迎加入PaddleClas技术交流群
+
+* 微信扫描二维码加入官方交流群，获得更高效的问题答疑，与各行各业开发者充分交流，期待您的加入。
+
+![](docs/images/joinus.png)
+
+
 ## 文档教程
 
 - [快速安装](./docs/zh_CN/tutorials/install.md)