code: public static Embedded embedded(final String rel,
                                      final HalRepresentation embeddedItem) {
          return new Embedded(singletonMap(rel, embeddedItem));
      }
docs: Create an Embedded instance with a single embedded HalRepresentations that will be rendered as a single
  item instead of an array of embedded items.
  
  @param rel the link-relation type of the embedded items
  @param embeddedItem the single embedded item
  @return Embedded
  
  @since 2.0.0