pageObject handles emptyPage
marking state changes
more prep for refactoring
Merge branch 'master' into ward/placeholder
handmade call graph to guide refactoring

See discussion in github issues.
https://github.com/fedwiki/wiki-client/issues/19
flag tooltip now pageObject responsibility
a row of pages is called a lineup
add pages to lineup as we render them
internal link can discard right side of the lineup
flipping through history changes lineup

I rewrote the logic here to avoid anything more
complicated that pushing or poping pages.

I struggled to find algorithm that was symetric
between old and new pages. Both loops now 
preserve the prefix (pages that are matching)
which I moved out of logic and into a variable.

This was expressed as an 'unless' statement but
coffeescript messed up the application of 
demorgan's law.
Merge branch 'master' into ward/placeholder
don't try to scroll in boundary case
we don't patch in missing array operations any more

This was only used once, very early. I've hunted
for the spot but can't find it. The error message
should be clear to anyone who knows that we've
removed this global modification.
enhancement to dialog has been left unfinished too long
move timestamp retrieval to pageObject
flipping through journal changes the lineup
distinguish cases where lineup changes
cleaner handling of newPage from future and template

This is the first operation that depends on the
lineup being correct. It makes sense that it 
should be first. It struggled (and still does some)
to pull all the pieces together.
don't remove $page.data('rev') until we know how it is used
revise the picture with latest changes