v2 includes some AFPUB tidying

After using this pocketmod myself, I tidied up the AFPUb templates. Basically reording and renaming layers, including a 4mm margin and adapting the paragraph spacing in each text box to suit both page margins and to take into account folding discrepancies (text shouldn’t be right on the borders of each text box, otherwise some text will be hard to read if it is too close to the fold).