Added support and badge for coveralls.io

Author: kucjac

.travis.yml

@@ -12,8 +12,10 @@ notifications:
   email: false
 
 before_script:
+  - go get github.com/mattn/goveralls
   - go install github.com/golangci/golangci-lint/cmd/golangci-lint
 
 script:
   - golangci-lint run       # run a bunch of code checkers/linters in parallel
-  - go test -race ./...  # Run all the tests with the race detector enabled
+  - go test -race ./...  # Run all the tests with the race detector enabled
+  - $GOPATH/bin/goveralls -service=travis-ci

README.md

@@ -1,6 +1,6 @@
 ![Neuron Logo](logo.svg)
 
-# Errors [![Go Report Card](https://goreportcard.com/badge/github.com/neuronlabs/errors)](https://goreportcard.com/report/github.com/neuronlabs/errors) [![GoDoc](https://godoc.org/github.com/neuronlabs/errors?status.svg)](https://godoc.org/github.com/neuronlabs/errors) [![Build Status](https://travis-ci.com/neuronlabs/errors.svg?branch=master)](https://travis-ci.com/neuronlabs/errors) ![License](https://img.shields.io/github/license/neuronlabs/errors.svg)
+# Errors [![Go Report Card](https://goreportcard.com/badge/github.com/neuronlabs/errors)](https://goreportcard.com/report/github.com/neuronlabs/errors) [![GoDoc](https://godoc.org/github.com/neuronlabs/errors?status.svg)](https://godoc.org/github.com/neuronlabs/errors) [![Build Status](https://travis-ci.com/neuronlabs/errors.svg?branch=master)](https://travis-ci.com/neuronlabs/errors) [![Coverage Status](https://coveralls.io/repos/github/neuronlabs/errors/badge.svg?branch=master)](https://coveralls.io/github/neuronlabs/errors?branch=master) ![License](https://img.shields.io/github/license/neuronlabs/errors.svg)
 
 Package errors contains simple golang error handling and classification primitives.