- `Rails.root` is a `Pathname`, so let's use `Rails.root.join`
- Clean up most of the remaining `File.join`s

DC DG; added LastThreeComments decorator so we don't have to load those comments when not needed (i.e. new profile pages)

and comment presenter

don't render page-viewer twice; last_post should actually get the last post posted, not the first one

phasing out app.user() for app.currentUser

fix #2627 (webfinger produces 500 error, and refactor a little to encapsulate into Webfinger object a bit more

DG DH; made acts_as_api play nice with backbonejs.  comments are semi-functional; stream elements use the StreamElement js widget (for now).

ms iz rendering nothing for hcard and webfinger if account is closed, not showing aspect dropdown if the user account is closed