[Elasticsearch] Trying to add initial cluster endpoints if all endpoints failed.
[Elasticsearch] Tiny style.
[Aux] Renamed noncoyable macro.
[Elasticsearch] Wording.
[Aux] Cyclic dependency resolved using template method.

But it's not so beautiful.
[Aux] Providing default constructor for null sink.
[Benchmarking] Added benchmark to measure full logging cycle.
[Elasticsearch] One task more.
[Elasticsearch] Some renamings done.
[Elasticsearch] Forgotten include added.
[Elasticsearch] Let the compiler do its job.

If the action is movable - it will forward it. Actually this change is needed for `boost::asio` event loop, which requires its tasks to be copyable.