Wrap native ES client for API call intercept

[dai-chen]

We added an ES client wrapper ESClient long time ago: https://github.com/opendistro-for-elasticsearch/sql/blob/1d945a8a59fe14f226c019b724722d0d57354259/src/main/java/com/amazon/opendistroforelasticsearch/sql/esdomain/ESClient.java.

We should pass it around and start to use it as a layer between our code and ES. The benefit includes capturing to convert ES exception in one place, providing consistent retry mechanism, avoid static class like LocalClusterState etc.

In future, we should build our ES domain layer around this client, for example, request builder, response and mapping parser (we already have Index/Type/FieldMappings).

[dai-chen]

We've added a storage layer in our new query engine with Elasticsearch client wrapped: #469.