Support multiple index queries

[IIIEII]

It would be nice to do several queries from different indexes.
Just remove Index Pattern dropdown and place it into Query DSL field. For example:

{
  "query_1": { "index-pattern": "index1-*", ... query body ... },
  "query_2": { "index-pattern": "index2-*", ... query body ... }
}

And then use response.query_1... and response.query_2...

I can do pull request for this functionality if you OK with conception.

[PhaedrusTheGreek]

I think that longer term, it would be interesting if Elasticsearch could initiate queries inside of a painless script, then process the results arbitrarily before returning them to the client. It seems that such a functionality could address this enhancement.

[IIIEII]

I believe Elastic team could do it someday, but now we don't have it. So I'm going to fork it anyway and make a pull request for you. Let me know if you have some ideas how to do it better.