The different way to handle UUID into __id and UUID into document

[akitoshka]

There are two different approachs how the mongo-connector handles UUID.
The first approach looks like into elastic2_doc_manager, doc-manager sets UUID into Elasticsearch as is, using default str method (with '-' delimiters)
The second approach looks like as into formatter, mongo-connector get hex value (without delimiters).
So we have different behaviors if we work with __id or UUID into doc.
It is unexpected behavior.

[akitoshka]

Pull request #737