Min doc count defaults to zeroeditBoth the histogram and date_histogram aggregations now have a default min_doc_count of 0instead of 1.histogram 과 date_histogram aggregation 둘 모두는 min_doc_count 의 기본값으로 1 대신에 0 을 가진다.Timezone for date fieldeditSpecifying the time_zone parameter in queries or aggregations on fields of type date must now be either an ISO 8601 UTC offset, or a timezone id. For examp..