exchange: have `pull` return the pulloperation object
We mimic what was done for `push` for similar reason. We are about to drop
`localrepo.pull` (for consistency with dropping `localrepo.push` and we better
have an API as extensible as `push` is.
Find explanations about localrepo.push removal in 4d52e6eb98ea.
# The 9mail to support patchbomb and other email wrappers
[email]
method = /bin/mercurial/9mail