orderingList component allows to reorder items in a list.
Ordering List could contain several columns in list representation. And it
also has strong keyboard support out of the box.
In this example you may select some songs (using the mouse and Ctrl/Shift keys) and move them
within the list using controls.
Content definition for this component is similar to any Iteration component.
Thus, all you need is to define collection in Ordering List value attribute
and iterate the collection in nested columns with var attribute.
In order to set initially selected rows or to process submitted selection,
use selection attribute.