private Slime getData() {
        if (request.returnValues().size() > 0) {
            if (data == null) {
                data = SlimeUtils.jsonToSlime(request.returnValues().get(0).asString());
            }
            return data;
        } else {
            return new Slime();
        }
    }
Contains response data for a slime response and methods for decoding the response data that
are common to all {@link Slime} based config requests.

@author Ulf Lilleengen
config/src/main/java/com/yahoo/vespa/config/protocol/SlimeResponseData.java