code: public static <K, V> EntryStream<K, V> of(Iterator<? extends Entry<K, V>> iterator) {
          return of(new UnknownSizeSpliterator.USOfRef<>(iterator));
      }
docs: Returns a sequential, ordered {@link EntryStream} created from given
  {@link Iterator}.
  
  <p>
  This method is roughly equivalent to
  {@code EntryStream.of(Spliterators.spliteratorUnknownSize(iterator, ORDERED))}
  , but may show better performance for parallel processing.
  
  <p>
  Use this method only if you cannot provide better Stream source (like
  {@code Collection} or {@code Spliterator}).
  
  @param <K> the type of stream keys
  @param <V> the type of stream values
  @param iterator an iterator to create the stream from.
  @return the new stream
  @since 0.5.1