Try to add item links within ES query directly.

[sharkinsspatial]

Currently we are manually processing the ES query results at the API level to add the relevant item links. This is inefficient and we should investigate the potential for performing some token replacement internally with the ES query execution for items.

[matthewhanson]

The drawback here is that this would be require duplicating code in every backend (assuming other non-elasticsearch backends eventually get created).

Do we have an idea of the actual performance hit here?