Bug 24080: Add payout option to patron account page

Bug 24080: Add payout option to patron account page

This enhancement adds a refined workflow to allow librarians to pay out
money to patrons and record these payouts on the patrons account.

The use case is that a patron has somehow accrued credit, through a
refund perhaps, and the library wants to be able to physically hand over
some money to balance the patrons account.

Test plan:
1) Undertake a series of transactions that result in some outstanding
   credit on a patrons account.
2) Note that a new 'Issue payout' button appears next to a credit with
   an outstanding balance (but only if your user has the payout
   permission or is a superlibrarian)
3) Click the 'Issue payout' button and a modal should appear
   pre-populated with the amountoutstanding.
4) You should be able to edit the amount you wish to payout, make
   payment or cancel.
5) Signoff

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>