small Incremental pull toy extension

[Pierre-Yves David]

I glued a small extension that allows incremental pull.This make initial 
clone of big repo easier using atomic group of 100 changesets. So when 
the pull is interrupted progress is not lost.

This is a very early and hacky version, but this may be useful to some 
people, so I'm sharing it. It helps me for initial clone for mozilla 
central on unreliable connection.

The right way to do this is to have native support in mercurial through 
the bundle2 format.

extension is available here: 
https://bitbucket.org/marmoute/hg-incremental-pull/overview

-- 
Pierre-Yves David