implement search_raw

[willkg]

It'd look like this:

   s = S().search_raw({'query': {'query_string': {'query': 'name:tester'}}})

where search_raw takes a dict and pretty much just passes it through to pyelasticsearch ElasticSearch.search().

Why have this? It allows people to do searches skipping over our API, but still getting back search results in a form that's helpful.

[gvigneron]

On a recent project, my approach was a S().search_raw() that set a variable _raw_search, and a simple if _raw_search at S()._build_query() (and I update S()._clone() to copy the new _raw_search, and create some tests).

I can make a pull request if you think it's the right approach.

[patrick91]

@gvigneron can you put the somewhere?

[patrick91]

This is my implementation: patrick91@c8be2ab

@willkg do you want me to submit a PR?

[willkg]

@patrick91 A PR would be super!