Add Go Report Card to README

README.md

@@ -1,4 +1,4 @@
-Hercules [![Build Status](https://travis-ci.org/src-d/hercules.svg?branch=master)](https://travis-ci.org/src-d/hercules) [![codecov](https://codecov.io/github/src-d/hercules/coverage.svg)](https://codecov.io/gh/src-d/hercules) [![GoDoc](https://godoc.org/gopkg.in/src-d/hercules.v3?status.svg)](http://godoc.org/gopkg.in/src-d/hercules.v3)
+Hercules [![GoDoc](https://godoc.org/gopkg.in/src-d/hercules.v3?status.svg)](http://godoc.org/gopkg.in/src-d/hercules.v3) [![Build Status](https://travis-ci.org/src-d/hercules.svg?branch=master)](https://travis-ci.org/src-d/hercules) [![codecov](https://codecov.io/github/src-d/hercules/coverage.svg)](https://codecov.io/gh/src-d/hercules) [![Go Report Card](https://goreportcard.com/badge/github.com/src-d/hercules)](https://goreportcard.com/report/github.com/src-d/hercules)
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 Amazingly fast and highly customizable Git repository analysis engine written in Go. Batteries included.