[ENHANCEMENT] deserialize to specific Hit type?

[0x8f701]

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[russcam]

This is related to #75 and #79.

The current way that I would recommend doing this is

#[macro_use]
extern crate serde_json;

use elasticsearch::{
    Elasticsearch, Error, SearchParts
};
use serde::Deserialize;
use serde_json::Value;

#[derive(Deserialize, Debug)]
pub struct Question {
    pub title: String
}

#[tokio::main]
async fn main() -> Result<(), Error> {
    let client = Elasticsearch::default();
    let response = client
        .search(SearchParts::Index(&["posts"]))
        .body(json!{
            {
                "query": {
                    "term": {
                        "type": "Question"
                    }
                }
            }
        })
        .send()
        .await?;

    let body: Value = response.json().await?;

    let docs: Vec<Question> = body["hits"]["hits"]
        .as_array()
        .unwrap()
        .iter()
        .map(|h| serde_json::from_value(h["_source"].clone()).unwrap())
        .collect();

    for doc in docs {
        println!("{}", doc.title);
    }

    Ok(())
}

I'm going to close this in order to solicit feedback on #75.