Bug 22802: Check item funds, order funds, and default funds when ordering from a...

Bug 22802: Check item funds, order funds, and default funds when ordering from a file

This patch tries to centralise the logic of order funds requirements into a single routine.
If propogates defaults down into items/order as necessary, it also prevents unsetting lower values if
a default is set.

To test:
1 - Populate 'MarcItemFieldsToOrder'
2 - Add to a basket from a file
3 - Use a file containing some item records with funds defined or not
4 - Confirm if all items have funds defined, you can order
5 - Confirm that setting the default for an order populates items and you can order
6 - Confirm that setting the default for all orders populates items if present/ order if not
7 - Confirm that if defaults are set the lower levels cannot be unset
8 - Try various settings and confirm all work as expected

Signed-off-by: Liz Rea <wizzyrea@gmail.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>