[O] indenting nested TODOs in agenda views

[Eric Abrahamsen]

What would it take to get an Agenda tags view that indented nested
TODOs? I've always been bothered by the fact that nested TODOs within a
subtree are all flattened for the agenda view, so sometimes it's hard to
tell that several TODOs all belong to one "bigger" TODO.

I guess it would have to go in `org-finalize-agenda-entries', after the
filter function is run, and somehow instead of the way org entries are
currently fed to the sorting function. Would this be a desirable option?

Eric