[Craft 5] Allow Neo fields to be reusable in field layouts

[turnstylerj]

What would you like to see added to or changed in Neo, and why?

We've been waiting for Craft 5 so we can re-use block fields. Now that Craft 5 is out, it sounds like this is only actually possible with field types that save content in the content table (i.e. not the new Matrix field).

I'm not sure if Neo meets that requirement, but if possible, this would be a killer feature for Neo on Craft 5.