Added waitUntilVisibleAfterRefresh and textsToWaitFor - both discussed with @witzig.

Page objects refactored to exploit textsToWaitFor if relevant.

Login tests refactored for the newer API.

Some additional tests in subscription. The rest at least included as "pending".

test/e2e/page-objects/user.js

@@ -0,0 +1,29 @@
+'use strict';
+
+const web = require('../lib/web');
+
+module.exports = {
+    login: web({
+        url: '/users/login',
+        elementsToWaitFor: ['submitButton'],
+        elements: {
+            usernameInput: 'form[action="/users/login"] input[name="username"]',
+            passwordInput: 'form[action="/users/login"] input[name="password"]',
+            submitButton: 'form[action="/users/login"] [type=submit]'
+        }
+    }),
+
+    logout: web({
+        requestUrl: '/users/logout',
+        url: '/'
+    }),
+
+    account: web({
+        url: '/users/account',
+        elementsToWaitFor: ['form'],
+        elements: {
+            form: `form[action="/users/account"]`,
+            emailInput: 'form[action="/users/account"] input[name="email"]'
+        }
+    }),
+};