[rfc] cherrypicking merge (revision range)

[Erik Bågfors]

> I'd like to hear what other people think. Do we want 'bzr merge -r X..Y'
> mean merge revisions 'X through Y' rather than 'merge the difference
> from X to Y'.

No please,
I find that very confusing as it behaves totally different than diff
(and perhaps other commands?) and very different from svn which I have
to deal with now.  Lot's of other people going to bzr will be used
with svn so keeping this the same is a good thing.

I think of revisions as "states".  so bzr merge -r X..Y, in my mind
means merge the diff between state X and state Y.

/Erik