Update readme.md

Author: binarywang

readme.md

@@ -2,9 +2,12 @@
 
 [![码云Gitee](https://gitee.com/binary/weixin-java-tools/badge/star.svg?theme=blue)](https://gitee.com/binary/weixin-java-tools)
 [![Github](http://github-svg-buttons.herokuapp.com/star.svg?user=Wechat-Group&repo=weixin-java-tools&style=flat&background=1081C1)](https://github.com/Wechat-Group/weixin-java-tools)
+[![GitHub release](https://img.shields.io/github/release/Wechat-Group/weixin-java-tools.svg)](https://github.com/Wechat-Group/weixin-java-tools/releases)
 [![Maven Central](https://img.shields.io/maven-central/v/com.github.binarywang/weixin-java-parent.svg)](http://mvnrepository.com/artifact/com.github.binarywang/weixin-java-parent)
 [![Build Status](https://travis-ci.org/Wechat-Group/weixin-java-tools.svg?branch=develop)](https://travis-ci.org/Wechat-Group/weixin-java-tools)
 [![使用IntelliJ IDEA开发维护](https://img.shields.io/badge/IntelliJ%20IDEA-提供支持-blue.svg)](https://www.jetbrains.com/?from=weixin-java-tools)
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
+
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 #### 支持包括微信支付、开放平台、公众号（包括订阅号和服务号）、企业微信/企业号、小程序等微信功能的后端开发。
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