Get closer to an accurate model of Windows timestamp changes.

Get closer to an accurate model of Windows timestamp changes.
"Normal" non truncate writes always cause the timestamp to
be set on close. Once a close is done on a handle this can
reset the sticky write time to current time also.
Updated smbtorture4 confirms this.
Jeremy.
(cherry picked from commit 7f9fe127ba31e6dd064d090d5ffc8eeb377627ab)