hgext3rd/__init__.py

paths: use `list_paths` in `hg paths`

Using common code will make it simpler to update the logic behind the path
definition and storage.

Differential Revision: https://phab.mercurial-scm.org/D10441

# name space package to host third party extensions
from __future__ import absolute_import
import pkgutil

__path__ = pkgutil.extend_path(__path__, __name__)