README.md

Java implementation of NAT type detection

Inspired by https://github.com/HMBSbige/NatTypeTester
Issue and pull request are welcomed

NAT类型探测的Java实现

参照了c#版的实现：https://github.com/HMBSbige/NatTypeTester
欢迎测试效果并反馈issue