git readme.md 文档头部写法

<p align="center">

<img src="http://q22ig8g6g.bkt.clouddn.com/java-min-logo.jpg" border="0" />

</p>

<p align="center">
    <strong>一种简单的，支持不同方案的高性能分布式锁</strong>
</p>

<p align="center">
    <a href="http://mvnrepository.com/artifact/com.baomidou/lock4j-spring-boot-starter" target="_blank">
        <img src="https://maven-badges.herokuapp.com/maven-central/com.baomidou/lock4j-spring-boot-starter/badge.svg" >
    </a>
    <a href="http://www.apache.org/licenses/LICENSE-2.0.html" target="_blank">
        <img src="http://img.shields.io/:license-apache-brightgreen.svg" >
    </a>
    <a>
        <img src="https://img.shields.io/badge/JDK-1.7+-green.svg" >
    </a>
    <a>
        <img src="https://img.shields.io/badge/springBoot-1.4+_1.5+_2.0+-green.svg" >
    </a>
</p>
<p align="center">
    QQ群:<a href="https://jq.qq.com/?_wv=1027&k=5tFhLhS" target="_blank">710314529</a>
</p>