Add links to Docker hub + Docker badges

Author: schnapster

README.md

@@ -39,5 +39,9 @@ Put an `application.yml` file in your working directory. [Example](https://githu
 
 Run with `java -jar Lavalink.jar`
 
+Docker images are available on the [Docker hub](https://hub.docker.com/r/fredboat/lavalink/).
+
+[![Docker Pulls](https://img.shields.io/docker/pulls/fredboat/lavalink.svg)](https://hub.docker.com/r/fredboat/lavalink/) [![Docker layers](https://images.microbadger.com/badges/image/fredboat/lavalink:dev.svg)](https://microbadger.com/images/fredboat/lavalink:dev "Get your own image badge on microbadger.com")
+
 # Acknowledgements
 This project contains modified code from https://github.com/sedmelluq/jda-nas v1.0.5