Merge pull request #480 from graph-gophers/fix-readme-build-status

README.md: Fix build status badge

Author: tonyghita

README.md

@@ -1,4 +1,4 @@
-# graphql-go [![Sourcegraph](https://sourcegraph.com/github.com/graph-gophers/graphql-go/-/badge.svg)](https://sourcegraph.com/github.com/graph-gophers/graphql-go?badge) [![Build Status](https://semaphoreci.com/api/v1/graph-gophers/graphql-go/branches/master/badge.svg)](https://semaphoreci.com/graph-gophers/graphql-go) [![GoDoc](https://godoc.org/github.com/graph-gophers/graphql-go?status.svg)](https://godoc.org/github.com/graph-gophers/graphql-go)
+# graphql-go [![Sourcegraph](https://sourcegraph.com/github.com/graph-gophers/graphql-go/-/badge.svg)](https://sourcegraph.com/github.com/graph-gophers/graphql-go?badge) [![Build Status](https://graph-gophers.semaphoreci.com/badges/graphql-go/branches/master.svg?style=shields)](https://graph-gophers.semaphoreci.com/projects/graphql-go) [![GoDoc](https://godoc.org/github.com/graph-gophers/graphql-go?status.svg)](https://godoc.org/github.com/graph-gophers/graphql-go)
 
 <p align="center"><img src="docs/img/logo.png" width="300"></p>