Add JSON Column Type

[markhuot]

This adds a native JSON column type. The nice thing about this is you can use Preparse to cache an arbitrary amount of data in to a JSON field and then have MySQL generated columns index on whatever keys you'd like out of that JSON. We're using this liberally to bubble some deeply nested relationships up to a grandparent so we can index/search/sort on it more easily.

/ht @pixleight for the work on this!

/note This is an updated PR from #90, which had some conflicts. This resolves those conflicts.

[markhuot]

bump. Any interest in this?

[jalendport]

Yes, very interested, just haven't had any time lately to review and accept the PR - give me a month or so and I'll get it merged! Thanks for your patience 🙏