obshashrange: cleanup 'valid' life cycle - reset is only called when we detect a strip, the on disk data are invalid, - after a reset, we should not keep using the data base connection, - after a write, the on disk data are valid.

# name space package to host third party extensions
from __future__ import absolute_import
import pkgutil
__path__ = pkgutil.extend_path(__path__, __name__)