Documentation badge updated

Author: pabloFuente

README.md

@@ -1,5 +1,5 @@
 [![License badge](https://img.shields.io/badge/license-Apache2-orange.svg)](http://www.apache.org/licenses/LICENSE-2.0)
-[![Documentation badge](https://readthedocs.org/projects/fiware-orion/badge/?version=latest)](http://openvidu.io/docs/home/)
+[![Documentation Status](https://readthedocs.org/projects/openviduio-docs/badge/?version=stable)](https://docs.openvidu.io/en/stable/?badge=stable)
 [![Docker badge](https://img.shields.io/docker/pulls/fiware/orion.svg)](https://hub.docker.com/r/openvidu/classroom-demo/)
 [![Support badge](https://img.shields.io/badge/support-sof-yellowgreen.svg)](https://groups.google.com/forum/#!forum/openvidu)