registry backup (and upgrade --force)

[Joshua Root]

On 2016-4-4 03:01 , Clemens Lang wrote:
> Josh's answer sounds like it's not that much effort. I don't know,
> however, I'm not very familiar with that part of MacPorts base.

I was more going for "Something could be done, but the situation is 
perhaps more complex than you think, so do your homework before you go 
changing anything." :)

But yeah, the actual implementation probably wouldn't be that hard, once 
one figures out what should in fact be done.

- Josh