Instead of retrieving an entire SearchHit, get just a reference and
postpone the document retrieval when assembling the final results.
Remove sort information from results to make them consistent.
Move TumblingWindow under the sequence package.
Co-authored-by: James Rodewig <james.rodewig@elastic.co>
(cherry picked from commit bccfbcd81f2f1d3552e95e4a9ee2618fb3059bd9)