Inherited tags

Release 2.0.6 is out, moving us one step closer to a typed system of topics. At least now the post command is a bit more DescriptorUnit-friendly. This is going to be a long, dragged-out process, so I'm happy to intersperse some other functunality--like TagMatches--which have immediate utility. On the other hand, I'm quite happy to have made some progress on DescriptorUnits. It's been like a black cloud hanging over my head.

Next up is 2.0.7--inherited tags. There is a real need for this, as otherwise tags need to be replicated to subordinate topics to be able to do intersection searches.

My first thought was to have 4 new commands, it, dit, fit and pit. The it command would list the inherited tags, while dit, fit and pit would work very much like d, f and p, except for allowing matches on the tags of ancestor topics.

My current thinking is to avoid having more commands, enhance the Drawer, Folder and Page displays to include inherited tags, and just move the added functionality into the d, f and p commands. This way we avoid some of the complexity, and the added functionality shouldn't interfere with the normal usage of d, f and p.