* Adding test.
* Verifies and fix issue 1668. This commit updates the previous behavior of the
On Demand stream support by return a value type (document_reference) instead
of a reference to a document. This allows us to bridge with the usually simdjson
error system, with its simdjson_result types.
* Minor reformat.
* Adds a test with initial tests passing.
* Adding an example.
Daniel Lemire