Move from Backbone.Router to react-router for Fuel for OpenStack

React doesn't play well with Backbone.Router. We need to get rid of it in favor of react-router which is created for React and makes routing of any nested levels very straightforward

Introduce InternJS framework for UI functional tests for Fuel for OpenStack

UI is currently covered with unit tests based on Casper what makes tests creation and debugging complicated. InternJS is more suitable for single-page web applications like Fuel UI.