mercurial changegroup.buildbot hook breaks with hg 1.0

[neomantra]

When transitioning from mercurial 0.9.5 to 1.0, the changegroup.buildbot broke.

The changelog API had changed:  http://selenic.com/repo/index.cgi/hg-stable/rev/9db7fd77417d

The fix, which makes no provision to support older mercurial versions is to take the current version of change/hgbuildbot.py and change line 86 from:

changeset=repo.changelog.extract(repo.changelog.revision(n))

to:

changeset=repo.changelog.read(n)

[Ben]

A patch is proposed in #328 and #335, please apply ...