[ARMedslack] Package auto? downgrade

[Stuart Winter]

> > I usually find that this is faster than performing a system upgrade and
> > also there's no residue from the previous installation.
> So you have to keep a list of all the configuration files you have altered?

No, I have a good memory.  However, most of the files I modify are ones
that I add into a new package which gets installed upon the new OS -
usually because I'd install the same package upon multiple machines and I
wanted a similar configuration on each.