item of the list trying to go upwards or if placed on the last item trying
to go downwards will "circulate" the selection marker to the last and first
item of the list respectively and not just do nothing.
Remark: Left/Right also applicable in some cases, e.g. thumbnail viewing mode.
This is a minor tweaking since with the Home/End buttons we can have 99% of the
suggested behaviour (or just a workaround).
