add badage

Author: gitgitcode

README.md

@@ -2,6 +2,7 @@
 
 [![Build Status](https://travis-ci.org/gitgitcode/alink.svg?branch=master)](https://travis-ci.org/gitgitcode/alink)
 [![Coverage Status](https://coveralls.io/repos/github/gitgitcode/alink/badge.svg?branch=master)](https://coveralls.io/github/gitgitcode/alink?branch=master)
+[![Go Report Card](https://goreportcard.com/badge/github.com/gitgitcode/alink)](https://goreportcard.com/report/github.com/gitgitcode/alink)
 - [ZH](#简介)
 
 Golang package to read href,video,title ...  tags from an HTML page。