Implement sub-object interleaving to compress BSON Documents.

Determine a depth-first ordering of scalar field within a parent document. The binary stream should be interleaved with operation bytes belonging to separate fields based on this order.

When a sub-field is out of values in current operation it will continue at next operation currently not used by any sub-stream. The ordering guarantees that this will belong to this sub-field.

Interleaving ends when a EOO literal is read.

Any change to the hierarchy of the parent BSON Document requires the interleaving to end. But it will re-start if a new BSON Document literal is written to the stream.