docs: public static MappingSet parseMappings(Map<String, Object> content, boolean includeTypeName) {
          Iterator<Map.Entry<String, Object>> indices = content.entrySet().iterator();
          List<Mapping> indexMappings = new ArrayList<Mapping>();
          while(indices.hasNext()) {
              // These mappings are ordered by index, then optionally type.
              parseIndexMappings(indices.next(), indexMappings, includeTypeName);
          }
          return new MappingSet(indexMappings);
      }