Bug 10419: (follow-up) patrons with fines should not be deleted

Bug 10419: (follow-up) patrons with fines should not be deleted

Test plan:
- add a fine for a patron
- verify the script does not delete this patron.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Works, script do not delete a patron with fines.
No koha-qa errors with all patches applied

Test
1) Added a fine to a patron
2) run script
3) reports condition
Trying to delete patron 5... Failed to delete patron 5: patron has 10.00 in fines
4) Patron is not deleted

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Passes all tests and QA script.

Tested various combinations of options:
./delete_patrons.pl
  Gives a helpful message about the use of the script.
./delete_patrons.pl -h
  Outputs useful information about the use of the script
  and its various options.
./delete_patrons.pl --category_code ST --library CPL
  Gives the correct results in numbers and deletion was done
  properly.

Also tested:
  --expired_before
  --not_borrowed_since
  -v

Testing various conditions where a delete should not occur:
- Patron has checkouts
  Patron is not in list of patrons to delete (x patrons to delete)
- Patron has fines
  Patron is still in list of patrons to delete (x patrons to delete)

Checked deleted patrons had been moved to deletedborrowers.

Notes about possible enhancements:
- only print the success message 'x patrons deleted' when confirm
  flag was set
- patrons with current checkouts are silently excluded from the number
  of patrons to be deleted. Printing the number with current checkouts
  might be helpful.

Changes made:
  Fixed a small error in the documentation: expired_date is expired_before.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>