Replacement of master/slave by primary/secondary:

• host-controller/src/main/java/org/jboss/as/host/controller/discovery/S3Discovery.java writes information by default to "/S3/master/jboss-domain-master-data"
  We need to rename this file and we have to evaluate the consequences of this change, so I've used a separated Jira for this change.
• Fix any affected test