docs: private TreeBuilder<ResourceMeta> configureConverterPlugin(TreeBuilder<ResourceMeta> builder, int index,
                                                                 Map<String, String> configProps) {
          String pref1 = getConverterConfigPrefix() + SEP + index;
          String pluginType = configProps.get(pref1 + SEP + TYPE);
          String pathProp = pref1 + SEP + PATH;
          String selectorProp = pref1 + SEP + RESOURCE_SELECTOR;
          String path = configProps.get(pathProp);
          String selector = configProps.get(selectorProp);
          if (null == path && null == selector) {
              throw new IllegalArgumentException("Converter plugin [" + index + "] specified by " + (pref1) + " MUST " +
                                                 "define one of: " +
                                                 pathProp + " OR " + selectorProp);
          }
  
          Map<String, String> config = subPropertyMap(pref1 + SEP + CONFIG + SEP, configProps);
          config = expandConfig(config);
          logger.debug("Add Converter[" + index + "]:"
                       + (null != path ? path : "/")
                       + "[" + (null != selector ? selector : "*") + "]"
                       + " " + pluginType + ", config: " + config);
  
  
          return buildConverterPlugin(builder, pluginType, path, selector, config);
      }