added version badge

README.md

@@ -11,6 +11,7 @@ You're going to love Zammad!
 
 ## Statusbadges
 
+- Current develop version: [![GitHub version](https://badge.fury.io/gh/zammad%2Fzammad.svg)](https://packager.io/gh/zammad/zammad)
 - Build: [![Build Status](https://travis-ci.org/zammad/zammad.svg?branch=develop)](https://travis-ci.org/zammad/zammad)
 - Code: [![Code Climate](https://codeclimate.com/github/zammad/zammad/badges/gpa.svg)](https://codeclimate.com/github/zammad/zammad) [![Coverage Status](https://coveralls.io/repos/github/zammad/zammad/badge.svg)](https://coveralls.io/github/zammad/zammad)
 - Docs: [![Documentation Status](https://readthedocs.org/projects/zammad/badge/?version=latest)](https://docs.zammad.org)