Remove sudo mode and add password confirmation when changing email address

closes #674

js/lib/Model.js

@@ -154,10 +154,13 @@ export default class Model {
 
     this.pushData(data);
 
+    const request = {data};
+    if (options.meta) request.meta = options.meta;
+
     return app.request(Object.assign({
       method: this.exists ? 'PATCH' : 'POST',
       url: app.forum.attribute('apiUrl') + this.apiEndpoint(),
-      data: {data}
+      data: request
     }, options)).then(
       // If everything went well, we'll make sure the store knows that this
       // model exists now (if it didn't already), and we'll push the data that