This is basically just for consistency, it's quite strange to see
multiple AK container types next to each other, some with and some
without the namespace prefix - we're 'using AK::Foo;' a lot and should
leverage that. :^)
If you tried to move a cursor down when the last row is selected, the
index becomes invalid without updating the selection. On the next
cursor movement the invalid index is then reset to {0, 0}, selecting
the first row instead.
