Simplification of the Bootstrap template

  - Resharper-powered refactoring to correct naming irregularities (tripel to triple, constants naming, etc.)
  - New ThemeHelper to simplify the conditional logic in Layout.cshtml & speed up template rendering.
  - Addition of a RegisterAppleLink helper to put AppleTouch icons in the page metadata.
  - Addition of a "FooterScript" zone to add analytics code as an HTML widget.