add release icon.

Author: aaronshan

README.md

@@ -1,4 +1,7 @@
-# hive-third-functions [![Build Status](https://travis-ci.org/aaronshan/hive-third-functions.svg?branch=master)](https://travis-ci.org/aaronshan/hive-third-functions)
+# hive-third-functions 
+
+[![Build Status](https://travis-ci.org/aaronshan/hive-third-functions.svg?branch=master)](https://travis-ci.org/aaronshan/hive-third-functions)
+[![Release](https://img.shields.io/github/release/aaronshan/hive-third-functions.svg)](https://github.com/aaronshan/hive-third-functions/releases)
 
 ## Introduction