Code review comment for lp:~mbp/bzr/391411-reconfigure-stacked

> I have some qualms about putting it into class Reconfigure though; this seems
> like the kind of thing we don't have an entirely satisfactory style for.
> Perhaps in this case the different types of reconfiguration should be
> different subclasses, rather than a bunch of variables on the instance...

I've put it into new Reconfigure-like classes to do this, and having done the other tweaks will submit this.