Bug 29102: Do not count patron's own hold against limits

Bug 29102: Do not count patron's own hold against limits

This patch makes three changes:
1 - The borrower's own holds are not counted towards HighHolds limit
2 - We exclude all hold counts from CanItemBeReserved
3 - Static mode should only decrease hold when over the decreaseLoanHighHoldsValue, not when equal

Previously a patron's hold could put the count over the threshhold, and
if the patron is only allowed 1 hold per record, and the hold wasn't found before
the checkout, it would make all items unholdable, thus lowering the theshhold for
dynamic HighHolds

To test:
 1 - Set sysaprefs:
     decreaseLoanHighHolds  - enable
     decreaseLoanHighHoldsDuration - 1
     decreaseLoanHighHoldsValue - 1
     decreaseLoanHighHoldsControl - "over the number of holdable items on the record" / dynamic
     decreaseLoanHighHoldsIgnoreStatuses - blank
 2 - Set circ rules to allow 1 hold per record and loan period of 5
 3 - Find/create a record with 3 items
 4 - Place a title level hold for two different patrons
 5 - Attempt to checkout item - note warning about high holds
 6 - Cancel checkout
 7 - Set decreaseLoanHighHoldsControl - "on the record" / static
 8 - Attempt checkout - note warning about high holds
 9 - Apply patch
10 - Checkout item - no warning
11 - checkin item, replace hold
12 - Set decreaseLoanHighHoldsControl - "over the number of holdable items on the record" / dynamic
13 - Checkout item - no warning
14 - prove t/db_dependent/DecreaseLoanHighHolds.t

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>