[build] Update readme, delete travis

Author: g3force

.travis.yml

@@ -1,4 +1,4 @@
-![travis build](https://travis-ci.org/g3force/ssl-game-controller.svg?branch=master "travis build status")
+[![CircleCI](https://circleci.com/gh/g3force/ssl-game-controller/tree/master.svg?style=svg)](https://circleci.com/gh/g3force/ssl-game-controller/tree/master)
 [![Go Report Card](https://goreportcard.com/badge/github.com/g3force/ssl-game-controller?style=flat-square)](https://goreportcard.com/report/github.com/g3force/ssl-game-controller)
 [![Go Doc](https://img.shields.io/badge/godoc-reference-blue.svg?style=flat-square)](http://godoc.org/github.com/g3force/ssl-game-controller)
 [![Release](https://img.shields.io/github/release/golang-standards/project-layout.svg?style=flat-square)](https://github.com/g3force/ssl-game-controller/releases/latest)