Upgrade submodules
Add default formatters for Au and Range
fmt! -> format!
Add a helper for ignoring the EOF condition so we don't crash
Other language changes
Remove unnecessary format!s
Store the Page's final URL before parsing

We were parsing URLs like

    //bits.wikimedia.org/static-1.22wmf22/skins/vector/images/search-ltr.png?303-4

as local filenames because HTMLImageElement::update_image didn't have a
current_url to pass to make_url().