scmutil: factor out transaction name lookup in registersummarycallback()
Add an inner txmatch function in registersummarycallback() factoring out the
logic to determine if the transaction matches a particular sources set. We'll
reuse this function to add some new report logic in the new changeset.
# name space package to host third party extensions
from __future__ import absolute_import
import pkgutil
__path__ = pkgutil.extend_path(__path__, __name__)