add loading indicator to feed-nifi-properties.ts
+
+<ng-template tdLoading [tdLoadingUntil]="feed.propertiesInitialized" tdLoadingStrategy="overlay" tdLoadingType="linear">
<form [formGroup]="form">
<div fxLayout="column" *ngIf="(mode=='INPUT' || mode == 'ALL')">
<ng-container *ngIf="!feed.readonly">
</ng-container>
</form>
-
+</ng-template>
