Bug 16889: Remove C4::Items::biblioitems_columns and use Koha::Biblioitems->columns...

Bug 16889: Remove C4::Items::biblioitems_columns and use Koha::Biblioitems->columns instead

Test plan:
Add new rule to the "Automatic item modifications by age" tools
(tools/automatic_item_modification_by_age.pl) and make sure the columns
of the biblioitems table are correctly displayed in the 'Conditions'
dropdown list.

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>