ES6: AvatarSelector and HeaderController - also includes support for controllers with

camelcase via an error message.

app/assets/javascripts/discourse/controllers/avatar-selector.js.es6

@@ -7,7 +7,7 @@
   @uses Discourse.ModalFunctionality
   @module Discourse
 **/
-Discourse.AvatarSelectorController = Discourse.Controller.extend(Discourse.ModalFunctionality, {
+export default Discourse.Controller.extend(Discourse.ModalFunctionality, {
 
   actions: {
     useUploadedAvatar: function() { this.set("use_uploaded_avatar", true); },

app/assets/javascripts/discourse/controllers/header.js.es6

@@ -6,7 +6,7 @@
   @namespace Discourse
   @module Discourse
 **/
-Discourse.HeaderController = Discourse.Controller.extend({
+export default Discourse.Controller.extend({
   topic: null,
   showExtraInfo: null,
   notifications: null,