* stable-2.14:
ElasticTestUtils: Set index.maxLimit as integer rather than string
ElasticConfigurationTest: Add tests for elasticsearch.maxRetryTimeout
ElasticConfigurationTest: Add tests for elasticsearch.prefix
ElasticConfigurationTest: Add tests for elasticsearch.{username,password}
ElasticConfiguration: Extract constants to statics
Elasticsearch: Simplify configuration of servers
Change-Id: Ic579d37734f285043f2d5ea9b764ec75cb485768