restructure assets to make room for new approach

* use sprockets 2.2.2.backport1 (see: https://github.com/rails/rails/issues/9492)
* use require.js via requirejs-rails
* manage future front-end assets via bower
* move old assets into archive directories
* modify old layouts to reference archived assets
* create new layout, app/views/layouts/application_future
* create new view, app/views/measures/new_dash, for displaying new dashboard markup