Switches client side templates to handlebars.

	modified:   Gemfile
	modified:   Gemfile.lock
	modified:   app/assets/javascripts/application.js
	modified:   app/assets/javascripts/backbone/apps/nav/list/list_view.js.coffee
	deleted:    app/assets/javascripts/backbone/apps/nav/list/templates/_nav.jst.eco
	new file:   app/assets/javascripts/backbone/apps/nav/list/templates/nav.jst.hbs
	renamed:    app/assets/javascripts/backbone/apps/nav/list/templates/navs.jst.eco -> app/assets/javascripts/backbone/apps/nav/list/templates/navs.jst.hbs
	modified:   app/assets/javascripts/backbone/config/marionette/renderer.js.coffee