Add support for secondary index on Elasticsearch via the REST API
using the Jest client [1].
Because Elasticsearch uses different version of Lucene we add another
maven_jar's in gerrit-elasticsearch BUCK. Fortunately both versions have
compatible API, this way we are able to compile and run Gerrit.
All tests for changes index passes, but they need to use Lucene's based
account index.
[1] http://www.searchly.com/documentation/developer-api-guide/java-jest/
TODO: Add support for online reindex
TODO: Add support for schema upgrades
Also-By: Janice Agustin <janice.agustin@ericsson.com>
Also-By: Olga Grinberg <olga.grinberg@ericsson.com>
Also-By: Dariusz Luksza <dluksza@collab.net>
Change-Id: I5e4fc08ce34d33c090c9e0bf320de1b17309f774
