post-new-merge delete old stuff megaticket about unison HOT 2 OPEN

I think we can delete all of these other than todo.

todo is meant to be the one-stop shop for orienting the user to what they need to fix up. (link tbd)
e.g. listing name conflicts, missing dependency names, failing merge pre-reqs, dependents of base.todo, and maybe some other stuff, probably including any non-patch-related stuff it may be doing today.

In the first version we can just have it list name conflicts (assuming it does this today) and list missing dependency names.

from unison.

Here is what todo does today:

1. Gets the set of "edited" (LHS) terms and types from the patch, computes the transitive closure of dependents of those things, and informs you about which ones you might want to fix up first (the "frontier" of that transitive closure, i.e. the nearest dependents to the "edited" set)
2. Tells you about the conflicted names in the namespace

from unison.