Bug 18547: On shelf holds allowed > "If all unavailable" ignores default hold policy

Bug 18547: On shelf holds allowed > "If all unavailable" ignores default hold policy

If in the circ rules matrix you set "On shelf holds allowed" to "If all unavailable",
default hold policy "From home library" is ignored.

Test plan:

- Have a test user from one branch (eg Centerville)

- Set "On shelf holds allowed" to "If all unavailable" for your patron and item
  category (or everyone and everything)
- For "Default checkout, hold and return policy", set hold policy to "From home library"
  -> make sure there is no "Default holds policy by item type" to override the setting

- Have two items for a record.
  1. An item with home branch same as test user (eg Centerville)
  -> check this item out to somebody else
  2. an item with a different home branch (eg Fairfield)
  -> available, not checked out
- Try to place a hold for your test user. Does not work.

- Apply the patch
- Try to place a hold. Should work now.

Followed test plan, worked as intended
Signed-off-by: Alex Buckley <alexbuckley@catalyst.net.nz>
Followed test plan in the intranet and OPAC, worked as intended.
With few assumptions made:
- when the hold works, should be on the item 1 (Centerville)
  item 2 is only there to trigger the bug
- the circ rules were identically setup on each branch and in "Standard rules for all libraries"
Signed-off-by: Victor Grousset <victor.grousset@biblibre.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>