Merge pull request #32 from masaruh/readme

Fix readme

Author: masaruh

README.md

@@ -17,6 +17,7 @@ You need to install a version matching your Elasticsearch version:
 | es-2.0.2        |     0.20.2         |
 | es-2.1.0        |     0.21.0         |
 | es-2.1.1        |     0.21.1         |
+| es-2.1.2        |     0.21.2         |
 | es-2.2.0        |     0.22.0         |