Add support for Elasticsearch 6.5.0

Feature: Issue 10038
Change-Id: Iea007c8188053dc5cf93e46f0638faca1960b09c
8 files changed
tree: 8ebc59a2160a36bc443667dfe9f1f4487bbd20bd
  1. gerrit-acceptance-tests/
  2. gerrit-elasticsearch/
  3. gerrit-pgm/