#263 Publish by proxy

[Kyle Hasselbacher]

As I understand it, when I publish something, I
duplicate the data I publish so that I end up sending
out twice as much data as I'm actually publishing. If
I'm on a slow link, that stinks.

I'd like to be able to send a block to a broker on a
fast link and ask it to duplicate it. That way, my
slow link isn't used as much. I send it out once, and
it ends up on the net twice.

As a requesting broker, I'd send the mojo needed to
cover the publication plus a little more for the
server's trouble.

As a serving broker, I need to make sure I don't spend
more on publication than was offered for the service.