Bug 21190: Add authentication logging to checkpw

Bug 21190: Add authentication logging to checkpw

Add optional logging for successful and failing login attempts in
checkpw.

Test plan:
Enable the preferences
Perform a good login and a bad attempt
Check action_logs

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jon Knight <J.P.Knight@lboro.ac.uk>
Signed-off-by: Michal Denar <black23@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>