Bug 15408: Remove fund's timestamp when cloning a budget

Bug 15408: Remove fund's timestamp when cloning a budget

To duplicate the budget, the function CloneBudgetHierarchy create a new budget
from the old without the parameter timestamp, so that the database generates a
new one.

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Added unit tests to patch

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Modified to run properly the QA tests

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>