Fix afterMove callback index on moveUp/moveDown

When using the moveUp/moveDown functions (either through user input or directly), the index passed to the afterMove callback is the index of the source page, rather than the destination page. Fix this issue, and deal with the edge case where the page might have looping enabled and the user might want to loop to the last page from the first page.

To demonstrate the issue, attach an afterMove callback to a page and inspect the indexes passed to this callback as you scroll through the pages. In addition, enable looping and inspect the indexes passed.