Implement redesign, refactor everything

- Write CSS for everything, update templates.
- Refactor discussion view. Stream is split into two components
(content and scrubber) which have their own responsibilities.
- Extract pane functionality into a mixin.
- Implement global “back button” system. You give a “paneable” target
to the application controller, the back button will modulate its
pane-related properties as necessary, and call an action when the
button is clicked.
- Extract welcome-hero into its own component.
- Lots of other general improvements/refactoring. The code is quite
well-commented so take a look!

ember/app/routes/index.js

@@ -0,0 +1,36 @@
+import Ember from 'ember';
+import Discussion from '../models/discussion';
+
+export default Ember.Route.extend({
+
+	setupController: function(controller, model) {
+		controller.set('model', model);
+
+		if ( ! model.get('length')) {
+			controller.set('resultsLoading', true);
+
+			controller.getResults().then(function(results) {
+				controller
+					.set('resultsLoading', false)
+					.set('meta', results.get('meta'))
+					.set('model.content', results);
+			});
+		}
+	},
+
+	model: function(params) {
+		var model = Ember.ArrayProxy.create();
+
+		return Ember.RSVP.resolve(model);
+	},
+
+	actions: {
+		queryParamsDidChange: function(newParams, params) {
+			var self = this;
+			Ember.run.scheduleOnce('afterRender', function() {
+				self.refresh();
+			});
+		}
+	}
+
+});