evaluate yyjsonr as replacement for jsonlite #436
Description
Split off from #433. Low priority.
yyjsonr is faster, and natively supports NDJSON and GeoJSON, which could be handy.
Would need to make sure we have the correct arguments specified because the default structure of yyjsonr output may not always match those we have had with jsonlite. It should be possible to set the parameters for 100% backward compatibility but, alternately, we might wish to "break" things internally as very few functions have JSON as the user-facing output.
Also, the performance benefits may not be realized for us as the JSON payloads of even a "large" SDA query or OSD are really not that large in the grand scheme of things..