Refactor the filter Elasticsearch to use our manticore client in the elasticsearch output

[ph]

Currently the filter elasticsearch is using the elasticsearch-ruby client, in the past we have encountered some thread safety issue with this gem and we have decided to create our own small wrapper to calls elasticsearch using the Manticore library in the Elasticsearch output.

We should evaluate and/or implement the same logic in the filter.

Goals:

• reuse code from the elasticsearch output
• consolidate plugin options.
• Slowly migrate to a Universal plugin model.