Well wiki has no pages you can turn. So this is the
equivalent to page/chapter break for the web world.
Since we don't know what kinds of pages there are or are not, page
breaks are useless. We do have syntax for a chapter break, though:
(NB: A page is a feature of layout and have no logical meaning, a
chapter is a feature of logical structure. That's why we have syntax
for one and not the other. If you want to worry about pages, the code
should go in a skin.)