Updated item_order management to take  into account deletion of beans.
Added new item_order related queries to BeanParameterBase in preparation of the implementation of arbitrary moves of beans with an itemOrder field.
Implementation of arbitrary move around of beans as ordered by their itemOrder field. Part 1 for unique itemOrder for the bean with no secondary field.
Implementation of arbitrary move around of beans as ordered by their itemOrder field. Part 2 for itemOrder-s for beans with secondary field.
Implementation of arbitrary move around of beans as ordered by their itemOrder field. Part 3 for itemOrder-s for beans with secondary field.
Correction of bug in implementation of arbitrary move around of beans as ordered by their itemOrder field.