code: public FilteredForestConfiguration withRenamedHost(String hostName, String targetHostName) {
      if ( hostName == null )       throw new IllegalArgumentException("hostName must not be null");
      if ( targetHostName == null ) throw new IllegalArgumentException("targetHostName must not be null");
      renames.put(hostName.toLowerCase(), targetHostName.toLowerCase());
      return this;
    }
docs: Rename hosts to network-addressable names rather than the host names known
  to the MarkLogic cluster.
  
  @param hostName the host to rename
  @param targetHostName the network-addressable host name to use
  @return this instance (for method chaining)