code: public static <N> TopLevelDocument<N> TopLevelDocument(final NamespaceBindings bindings,
                                                           final N type,
                                                           final URI identity) {
      return TopLevelDocument(bindings, type, identity, Datatree.<N>NamedProperties());
    }
docs: Factory for {@link TopLevelDocument}.
  
  <p>
  This builds a new TopLevelDocument using the supplied data.
  </p>
  
  @param bindings    the namespace bindings
  @param type        the type of the document
  @param identity    the identity of the document
  @param <N>         the property name type
  @return  a new TopLevelDocument instance