Add support for pagination in queries with dynamodb.

Actually, when you set "limit" in Query or Scan methods, the first elements are obtained. This could be the first page. but there is no method that enables you obtain the second or third page.

Maybe, you can add a GetPage method, that returns a collection wrapper, inherited from Collection<T>. This wrapper could have the last evaluated key.

Then, GetPage method, could accept a query or scan expression, a page size and the last evaluated key

This could be very usefull for applications that needs paginate some results but don't need retrieve all data from database. This allows too a better use of database resource.

Thanks