Test the correct behavior of the "Midnight" and setDiff methods.
Especially to keep the time when switching from hidden time (midnoght)
back to shown time.
When XCA started in 2002, there were no C++ initializers.
Drop explicit initializers from the constructors.
- Fix indentations of section declarators.
- Replace NULL by nullptr when feasible.
- Sort private section: properties first, then methods.
- Only once set notBefore to "now" when creating Cert-renewal
or NewCert dialog.
- Apply-time button now always uses the current value from notBefore
and adds the time-span without resetting notBefore
- Checking "midnight" now immediately modifies the dates.
Unchecking "midnight" now recovers the old value
- The seconds are always set to 00, since they can't be set via
the DateTime dialog anyway
- CRL generation now too allows to use midnight and time ranges
and uses GENERALIZED time if the date is out of range for UTCTIME
(same logic as for certificates)
