add travis

.travis.yml

@@ -0,0 +1,7 @@
+language: go
+
+go:
+  - "1.12"
+
+env:
+  - GO111MODULE=on

README.md

@@ -1,4 +1,4 @@
-# go-snark [![Go Report Card](https://goreportcard.com/badge/github.com/arnaucube/go-snark)](https://goreportcard.com/report/github.com/arnaucube/go-snark)
+# go-snark [![Go Report Card](https://goreportcard.com/badge/github.com/arnaucube/go-snark)](https://goreportcard.com/report/github.com/arnaucube/go-snark) [![Build Status](https://travis-ci.org/arnaucube/go-snark.svg?branch=master)](https://travis-ci.org/arnaucube/go-snark)
 
 zkSNARK library implementation in Go