compat: fix instabilities compat
We added an instabilities method for old version of Mercurial. But we returned
an old value for orphan changesets, the one before the big evolve renaming.
Fix the return value to match the new return values.
# name space package to host third party extensions
from __future__ import absolute_import
import pkgutil
__path__ = pkgutil.extend_path(__path__, __name__)