Added Header tests

Change-Id: I331f9d1f2f65317e2af59b64fd389e7034dc3a3f
diff --git a/src/app/core/header/header.ts b/src/app/core/header/header.ts
index c91ef5f..20fbc3c 100644
--- a/src/app/core/header/header.ts
+++ b/src/app/core/header/header.ts
@@ -3,7 +3,7 @@
 import {IWSEvent} from '../../datasources/websocket/global';
 import {IStoreService} from '../../datasources/stores/synchronizer.store';
 
-interface INotification extends IWSEvent {
+export interface INotification extends IWSEvent {
   viewed?: boolean;
 }