Add role alert to toasts

For accessibility reasons, 'role="alert" is required for toast
messages. This notifies screen readers that an error or success
message has appeared. Adds a service layer for toast messages
that adds the role attribute to the message.

Change-Id: Ic4dbf5556337eea589de5692c1b4c3323e771813
Signed-off-by: beccabroek <beccabroek@gmail.com>
diff --git a/app/index.js b/app/index.js
index 2313016..c9fed83 100644
--- a/app/index.js
+++ b/app/index.js
@@ -31,6 +31,7 @@
 import services_index from './common/services/index.js';
 import constants from './common/services/constants.js';
 import dataService from './common/services/dataService.js';
+import toastService from './common/services/toastService.js';
 import api_utils from './common/services/api-utils.js';
 import userModel from './common/services/userModel.js';
 import apiInterceptor from './common/services/apiInterceptor.js';