Only showing content previews if they are different than the title.
Fixing Full screen with single story mode.
Merge branch 'master' into fonts

* master:
  Fixing Full screen with single story mode.
  Only showing content previews if they are different than the title.
Adding Gotham Narrow, Sentinel, Whitney, and Chronicle.
Adding line spacing options.
Line spacing icons.
Adding single story preference.
Removing dupe preferences that now live in style popover.
Adding premium explainer (and disabling fonts) for non-premiums.
Adding H&FJ fonts.
Dev fonts.
Moving fonts.
Fixing title size, fonts in List view, date and content preview colors, and helvetica size.
Little less dark story date on unread west-side.
Moving fonts to www.