fetch resume support

[Oliver Eikemeier]

Frank Laszlo wrote:

> I was thinking about this the other evening when I recieved an email 
> from Trevor Johnson about the SIZE now incorporated into the distinfo. 
> With this in place, it would be quite easy to add support for resumable 
> distfile fetching. I would be more than happy to write a patch for 
> bsd.port.mk for this, but I would like to see how the community responds 
> to it. What do you all think?

Since bsd.port.mk already calls fetch with -Rr, what would you want to patch?
Btw, how does this relate to SIZE?

-Oliver