Revert "Toggle/multi select mode - also add handler for clearing selection when clicking outside item"

This reverts commit ea50c036fe9284c2ca97a5f514a8dd652046c5d8.
Revert "When click is made inside knockout.selection area but not on an item, de-select all"

This reverts commit b62cb7fdf8387ec3bbbcb3af19ce8782b6facd3d.