Comment how we're remembering form vals

src/components/structures/login/Registration.js

@@ -54,6 +54,13 @@ module.exports = React.createClass({
         return {
             busy: false,
             errorText: null,
+            // We remember the values entered by the user because
+            // the registration form will be unmounted during the
+            // course of registration, but if there's an error we
+            // want to bring back the registration form with the
+            // values the user enetered still in it. We can keep
+            // them in this component's state since this component
+            // persist for the duration of the registration process.
             formVals: {
                 email: this.props.email,
             },