Enabled --prod mode for GUI2 - refactored modules

Change-Id: I224fe9564cb225b9ebaed0a43281de54ec6eb274
diff --git a/web/gui2/src/main/webapp/app/fw/util/ee.service.ts b/web/gui2/src/main/webapp/app/fw/util/ee.service.ts
index c16e4d1..8e1d87c 100644
--- a/web/gui2/src/main/webapp/app/fw/util/ee.service.ts
+++ b/web/gui2/src/main/webapp/app/fw/util/ee.service.ts
@@ -19,7 +19,9 @@
 /**
  * ONOS GUI -- Util -- EE functions
  */
-@Injectable()
+@Injectable({
+  providedIn: 'root',
+})
 export class EeService {
 
   constructor(