Updates to use latest Haystack 4 standard. This includes...
935: simplify how choices work for the common case to so that they work like all other tags
936: redesign how choices work for the complicated specialization use case via a new design pattern using the of tag
938: finalize the question mark inference operator in filter syntax
939: remove the equipFunction taxonomy until we learn more
Overall the main biggest changes are...
Reworked choices (minor).
Refactor how defs are used in the automated tests. Switched from using hard coded files. This will make it easier for future changes to defs.
Reworked relationship haystack filter query.
Removed implied tags support. It was an experiment and no-one uses it.