Configuring ingestion to default to pushing metadata so controllers do not always pull segments for metadata

From Slack:
> joey: the controller is pulling the entire segment. Does that happen for every segment? Is it just pulling it to grab the metadata, or does it persist additional data?
> That seems like a gnarly bottleneck if we're pushing TBs of data from a Spark app.

> kishore: its just pulling it for metadata
> there is a way to push the metadata as well
> so that it does not pull the entire segment
> we should make that the default

cc @kishoreg