Bug 19351: Add items.copynumber to the checkouts table

Bug 19351: Add items.copynumber to the checkouts table

This adds the items.copynumber to the checkouts table in the
patron account in the staff interface.

To test:
- Apply patch
- Check out some items with and without copy number in the item
  to any patron
- In the checkouts table on the Checkouts and Details tabs:
- Verify that a new column shows 'copy no' shows after 'call no'
- Verify the information displays correctly
- Verify that the column configuration settings for the new column works

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>