Prevent load options from being passed to ElasticSearch

WebMock can't [parse][] the load/include params that get sent through to ElasticSearch. Rather than fixing WebMock I've opted for the simpler option of removing the load options from the generated search URL.

**N.B.** The tire build was [failing][] when I cloned the repo.

I'm going to install Tire from this branch and test whether this resolves the issue with WebMock specifically.

[parse]: https://github.com/bblimke/webmock/blob/master/lib/webmock/util/query_mapper.rb#L96
[failing]: https://travis-ci.org/karmi/tire