Merge pull request #188 from datastax/readme_updates

Readme updates

Author: msmygit

README.md

@@ -1,5 +1,6 @@
 [![License Apache2](https://img.shields.io/hexpm/l/plug.svg)](http://www.apache.org/licenses/LICENSE-2.0)
 [![Star on Github](https://img.shields.io/github/stars/datastax/cassandra-data-migrator.svg?style=social)](https://github.com/datastax/cassandra-data-migrator/stargazers)
+![GitHub release (with filter)](https://img.shields.io/github/v/release/datastax/cassandra-data-migrator?label=latest%20release&color=green&link=!%5BGitHub%20release%20(with%20filter)%5D(https%3A%2F%2Fimg.shields.io%2Fgithub%2Fv%2Frelease%2Fdatastax%2Fcassandra-data-migrator%3Flabel%3Dlatest%2520release%26color%3Dgreen))
 
 # cassandra-data-migrator