chore(docs): Adding ansible galaxy install

Author: hypery2k

README.md

@@ -3,3 +3,7 @@
 [![Build Status](https://travis-ci.org/ContinuousSecurityTooling/ansible-role-secure-docker.svg?branch=master)](https://travis-ci.org/ContinuousSecurityTooling/ansible-role-secure-docker)
 
 > Main purpose is to prevent docker containers to expose ports via iptables port-forward to non-local interfaces
+
+```
+ansible-galaxy install continuoussecuritytooling.secure_docker
+```