Shared wisdom toolbar

Adds a toolbar to the top of all pages, which pulls in related ophan/ad/etc data about the page, using @gregdetre [api](http://blackandwhite/pageview/dynamic/?url=http://m.guardian.co.uk/lifeandstyle). 

API only available within the building, and toolbar only appears when `shared-wisdom-toolbar` userPref is switched on

NB: further incentive for lazy-loading of js/css