Option to include full list of hits

[wolfgang-braun]

Background information

We needed to process the full list of hits that the elastic search plugin retrieved, but the plugin is design to only assign fields and not the whole result set.

Feature description

Setting include_hits to true (it defaults to false) will cause the plugin to add the hits to [@metadata][hits].

[cla-checker-service]

❌ Author of the following commits did not sign a Contributor Agreement:
dce942f, 871008c, ac91a1a

Please, read and sign the above mentioned agreement if you want to contribute to this project

[wolfgang-braun]

@ph I did sign the contributor agreement.