Redesigned border pieces to make it easier to use thin notepads.

In the previous design, once the notepad becomes thinner than the wooden
pieces, it would become impossible to pull a note up by its edge.  This
modification changes the four border pieces into corners only, leaving gaps
between each so a finger can get at the edge.  In doing so, also eliminated
four rivets in that area, since they no longer pass through border pieces and
would just get in the way of finger access.