code: public static <T, C extends Collection<T>> Pair<Integer, C> page(long start, long howMany, Collection<T> in, C out) {
          return Pair.of(in.size(), Consumers.all(Filtering.slice(start, howMany, in), out));
      }
docs: Creates a page view of a collection adding elements to the out
  collection.
  
  @param <T> the element type parameter
  @param <C> the collection type parameter
  @param start the index where the page starts
  @param howMany the page size
  @param in the iterable to be sliced
  @param out the output collection
  @return a pair containing the iterator size and the requested page