Reveresed long-click and short-click actions for the library.
Fixed the page-offset calculation.

This is a fix for #299 where too much white space was used at the bottom
of the page. The error was caused by subtracting both the margin and the
space used by the page number.
Added algorithm version.

Since we changed the algorithm, all pagenumbers calculated with the old
algorithm need to be recalculated. By adding this field we can determine
this.
Fixed bug where reversal of click / long click didn't work.
Now actually saves the algorith number :)