HSEARCH-1494 &  HSEARCH-1092

Addresses the above issues.

It introduces `IndexedEmbedded#includeEmbeddedObjectId` as flag to explicitly control the embedded object id. If the id is explicitly listed via `includePaths` it still gets included. I think this approach had so far most support.

What is not addressed yet, is whether the default for the `IndexedEmbedded#depth` parameter should change to 0. However, this should probably be addressed in a separate issue anyways.


lots of nice improvements as well, but ideally should be in a separate commit as they are not related to the issue ;-)
(not a blocker at all)