re-factor all the audit source objects

src/auditsource.js

@@ -1,5 +1,15 @@
 'use strict';
 
 exports = module.exports = {
-    CRON:  { userId: null, username: 'cron' }
+    CRON:  { userId: null, username: 'cron' },
+    HEALTH_MONITOR: { userId: null, username: 'healthmonitor' },
+    SYSADMIN: { userId: null, username: 'sysadmin' },
+    TASK_MANAGER: { userId: null, username: 'taskmanager' },
+
+    fromRequest: fromRequest
 };
+
+function fromRequest(req) {
+    var ip = req.headers['x-forwarded-for'] || req.connection.remoteAddress || null;
+    return { ip: ip, username: req.user ? req.user.username : null, userId: req.user ? req.user.id : null };
+}