Bug 17309 - Renewing and HomeOrHoldingBranch syspref

Bug 17309 - Renewing and HomeOrHoldingBranch syspref

The AddRenewal subroutine currently uses the circulation rules for the branch
stored in the Issues table (which is the holding branch) when calculating the new due date.

This patch replaces using the branch from the Issues table with the branch
specified by the HomeOrHoldingBranch syspref.

To test:
1. Set up 2 branches, Branch1 and Branch2
2. Set up a loan rule in Branch1 for DVDs with a 21 day loan period and a
   21 day renewal period.
3. Set up a loan rule in Branch2 for DVDs with a 14 day loan period and a
   14 day renewal period.
4. Checkout a DVD belonging to Branch1 while logged into Branch2. It will
   receive the correct 21 day loan period.
5. Renewing the same DVD while logged into either Branch1 or Branch2
   will give a 14 day due date, rather than 21 days.
6. Checkout a DVD belonging to Branch2 while logged into Branch1. It will
   receive the correct 14 day loan period.
7. Renewing the same DVD while logged into either Branch1 or Branch2
   will give a 21 day due date, rather than 14 days.
8. Apply the patch and repeat steps 4-7. The correct due date should be given
   when the item is renewed, regardless of where it is checked out or renewed.

This update removes reassignment of $branch variable.

Signed-off-by: Cédric Vita <cedric.vita@dracenie.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>