Added badges in readme file

README.md

@@ -1,8 +1,9 @@
 # go-mysql-server
-
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
 <a href="https://travis-ci.org/src-d/go-mysql-server"><img alt="Build Status" src="https://travis-ci.org/src-d/go-mysql-server.svg?branch=master" /></a>
 <a href="https://codecov.io/gh/src-d/go-mysql-server"><img alt="codecov" src="https://codecov.io/gh/src-d/go-mysql-server/branch/master/graph/badge.svg" /></a>
 <a href="https://godoc.org/github.com/src-d/go-mysql-server"><img alt="GoDoc" src="https://godoc.org/github.com/src-d/go-mysql-server?status.svg" /></a>
+[![Issues](http://img.shields.io/github/issues/src-d/go-mysql-server.svg)](https://github.com/src-d/go-mysql-server/issues)
 
 **go-mysql-server** is a SQL engine which parses standard SQL (based on MySQL syntax), resolves and optimizes queries.
 It provides simple interfaces to allow custom tabular data source implementations.