Bug 21915: Add a cli script to reconcile balances

Bug 21915: Add a cli script to reconcile balances

This patch adds a CLI script, reconcile_balances.pl that takes care
of calling the reconcile operation for all patrons that have outstanding
credits.

A weird situation has been spotted in the wild, in which a debit ends up
actually being a credit, because amount outstanding is tweaked in
dropbox-mode returns. Until we figure what to do about that (probably a
new account type, etc), we catch any exceptions and warn about the
situation.

To test:
- Have patrons with outstanding credits and debits
- Run the script:
  $ kshell
 k$ perl misc/cronjobs/reconcile_balances.pl --verbose
=> SUCCESS: Notice patrons got their balances reconciled, and useful
            information is output.
- Add new outstanding credits and debits to patrons you con easily
identify
- Run:
 k$ perl misc/cronjobs/reconcile_balances.pl
=> SUCCESS: Notice balances are reconciled, but no output
- Run:
 k$ perl misc/cronjobs/reconcile_balances.pl --help
=> SUCCESS: Usage information is printed.
- Sign off :-D

Sponsored-by: ByWater Solutions
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>