phases: allow registration and boundary advancement with revision sets
The core internals either use revision sets already or can trivially use
them. Use the new interface in cg1unpacker.apply to avoid materializing
the list of all new nodes as it is normally just a revision range. This
avoids about 67 Bytes / changeset on AMD64 in peak RSS.
Differential Revision: https://phab.mercurial-scm.org/D9232
from __future__ import absolute_import
import pkgutil
__path__ = pkgutil.extend_path(__path__, __name__)