code: public static <E> Iterator<E> atMostLast(int howMany, Iterator<E> from) {
          return new AtMostMemoryIterator<E>(from, howMany);
      }
docs: Creates an iterator yielding at most last n elements from the source
  iterator. E.g:
  <code>atMostLast(4, [1, 2, 3]) -> [1, 2, 3]</code>
  <code>atMostLast(2, [1, 2, 3]) -> [2, 3]</code>
  
  @param <E> the iterator element type
  @param howMany number of elements to be yielded (at most)
  @param from the source iterator
  @return the resulting iterator