add travis ci badge

Author: bahmutov

Diff for: .npmrc

@@ -0,0 +1,4 @@
+registry=http://registry.npmjs.org/
+save-exact=true
+progress=false
+package-lock=false

Diff for: README.md

@@ -1,6 +1,6 @@
 # vue-hackernews-2.0
 
-[![Greenkeeper badge](https://badges.greenkeeper.io/bahmutov/vue-hackernews-2.0.svg)](https://greenkeeper.io/)
+[![Greenkeeper badge](https://badges.greenkeeper.io/bahmutov/vue-hackernews-2.0.svg)](https://greenkeeper.io/) [![Build Status](https://travis-ci.org/bahmutov/vue-hackernews-2.0.svg?branch=master)](https://travis-ci.org/bahmutov/vue-hackernews-2.0)
 
 HackerNews clone built with Vue 2.0 + vue-router + vuex, with server-side rendering.