Bug 15939: Action logs - Do not default dates to today

Bug 15939: Action logs - Do not default dates to today

When accessing the modification logs from a link that does not
explicitly set the to and from dates (e.g., from patron or bib details),
no results are displayed unless the object had an action occur during
the current day.

This is a side-effect of commit 5dceb851 for bug 13813.

Test plan:
- View the modification logs of a record which has already been modified
(/tools/viewlog.pl?do_it=1&modules=CATALOGUING&action=MODIFY&object=XXX)
=> Without this patch, you won't see any logs (unless you have modified
the record today)
=> With this patch, the behavior is the same as prior bug 13813 (you can
check in 3.20.x), you will see all logs

Signed-off-by: Galen Charlton <gmcharlt@gmail.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Brendan Gallagher brendan@bywatersolutions.com