Ok, I'm trying to get into a good routine where I keep ikiwiki updated for my site.
The plan is to keep a local (partial) git clone, and rebuild from tagged release commits.

I started out with 3.20140831, more or less like this:

    $ git clone ...
    $ git checkout 3.20140831
    $ perl Makefile.PL PREFIX=$HOME/blah
    $ make
    $ make install
    $ cd ~/my-wiki-admin-stuff
    $ ~/blah/bin/ikiwiki --dumpsetup=my.wiki.setup
    $ vi my.wiki.setup
    $ ~/blah/bin/ikiwiki --setup my.wiki.setup

So far so good. Fast-forward (heh) to 3.20140916:

    $ git fetch ...
    $ git merge --ff-only FETCH_HEAD
    $ git checkout 3.20140916
    $ perl Makefile.PL ... ; make ; make install
    $ cd ~/my-wiki-admin-stuff ; ~/blah/bin/ikiwiki --setup my.wiki.setup

This happened to work, but in general if the new ikiwiki version had new
setup options I needed to know about, I wouldn't necessarily find out, and
I could be running the new version with something important taking an
inappropriate default because I didn't add it to the setup file.

What I'm looking for is some sort of

    ikiwiki --read-my-current-setup-file-and-write-one-with-the-same-config-but-with-new-options-shown-and-commented

command.

Will `ikiwiki --changesetup setupfile` do what I'm looking for?

I'm hoping for something simple that takes care of the way the setup sections are conditional
(so `--dumpsetup` doesn't even show you `git` options unless it knows `rcs=git`, so ideally it
would look in the current setup to learn what to dump).

How are other folks handling this routinely?