Lukas Wegmann

Add native support for SQL and EQL queries

2

For benchmarking SQL and EQL queries we're currently using custom runners (see [here for EQL](https://github.com/elastic/rally-tracks/blob/master/eql/track.py) and [here for SQL](https://github.com/elastic/rally-tracks/pull/216)). As @danielmitterdorfer [pointed out](https://github.com/elastic/rally-tracks/pull/216#discussion_r747310975), there is some potential to improve the...