Bug 25665: (Bug 23382: (RM follow-up) Revert "hours_between should match...")

Bug 25665: (Bug 23382: (RM follow-up) Revert "hours_between should match...")

This reverts commit a693c7243c23f888e2fad38a4fff9f37ff4a9301 which
caused regressions.

The original loop compared start date to end date and iterated all the
way to start date equals end date. The alternate implimentation
inadvertantly looped from start date, skipped the first day then
iterated up to one day beyond end date.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>