Update project introduction.

README.md

@@ -3,7 +3,7 @@ Sky Walking
 
 <img src="https://sky-walking.github.io/page-resources/3.0/skywalking.png" alt="Sky Walking logo" height="90px" align="right" />
 
-SkyWalking: Large-Scale Distributed Systems Tracing Infrastructure, also known Distributed Tracer.
+SkyWalking 3.x: APM for Distributed Systems, also known Distributed Tracing System.
 
 [![Build Status](https://travis-ci.org/wu-sheng/sky-walking.svg?branch=master)](https://travis-ci.org/wu-sheng/sky-walking)
 [![Coverage Status](https://coveralls.io/repos/github/wu-sheng/sky-walking/badge.svg?branch=master)](https://coveralls.io/github/wu-sheng/sky-walking?branch=master)
@@ -11,7 +11,7 @@ SkyWalking: Large-Scale Distributed Systems Tracing Infrastructure, also known D
 [![codebeat badge](https://codebeat.co/badges/579e4dce-1dc7-4f32-a163-c164eafa1335)](https://codebeat.co/projects/github-com-wu-sheng-sky-walking)
 [![Join the chat at https://gitter.im/sky-walking/Lobby](https://badges.gitter.im/sky-walking/Lobby.svg)](https://gitter.im/sky-walking/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![OpenTracing-1.0 Badge](https://img.shields.io/badge/OpenTracing--1.0-enabled-blue.svg)](http://opentracing.io)
-[![Release Version](https://img.shields.io/badge/stable-2.3--2017-brightgreen.svg)](https://github.com/wu-sheng/sky-walking/releases)
+[![Release Version](https://img.shields.io/badge/tesing-3.0--2017-yellow.svg)](https://github.com/wu-sheng/sky-walking/releases)
 
 
 * Auto-instrumentation mechanism, **no need to CHANGE any application source code**. Supported [frameworks](https://github.com/wu-sheng/sky-walking/wiki/3.0-supported-list).