Set up responsive admin layout

ember/admin/app/components/user-dropdown.js

@@ -0,0 +1,23 @@
+import Ember from 'ember';
+
+import HasItemLists from '../mixins/has-item-lists';
+import DropdownButton from './ui/dropdown-button';
+
+var precompileTemplate = Ember.Handlebars.compile;
+
+export default DropdownButton.extend(HasItemLists, {
+  layoutName: 'components/application/user-dropdown',
+  itemLists: ['items'],
+
+  buttonClass: 'btn btn-default btn-naked btn-rounded btn-user',
+  menuClass: 'pull-right',
+  label: Ember.computed.alias('user.username'),
+
+  populateItems: function(items) {
+    var self = this;
+
+    this.addActionItem(items, 'logout', 'Log Out', 'sign-out', null, function() {
+      self.get('parentController').send('invalidateSession');
+    });
+  }
+})