include system-announcement warning for construction times etc.

src/app/app-root/login/login.component.html

@@ -16,6 +16,7 @@
     </form>
     <p style="color: chocolate"><b>{{ problemText }}</b></p>
     <p style="color: chocolate" *ngIf="!mds.isApiValid"><b>Die Verbindung mit dem Server ist nicht möglich.</b></p>
+    <alert *ngIf="systemAnnouncement !== '-'" level="warning" [text]="systemAnnouncement"></alert>
   </mat-card>
 
   <mat-card fxFlex="0 0 400px" class="mat-card-gray">

src/app/app-root/login/login.component.ts

@@ -26,6 +26,8 @@ export class LoginComponent implements OnInit, OnDestroy {
     pw: new FormControl('')
   });
 
+  systemAnnouncement: string;
+
   constructor(
     public mds: MainDataService,
     public cts: CustomtextService,
@@ -39,6 +41,9 @@ export class LoginComponent implements OnInit, OnDestroy {
     this.routingSubscription = this.route.params.subscribe(params => {
       this.returnTo = params.returnTo;
     });
+    setTimeout(() => { // the timeout is  avery temporary fix.- after upgrading to iqb-components 3, it can be removed
+      this.systemAnnouncement = this.cts.getCustomText('system_announcement', '-');
+    }, 500);
   }
 
   login(): void {

src/app/app.module.ts

@@ -37,6 +37,7 @@ import { StatusCardComponent } from './app-root/status-card/status-card.componen
 import { TestStarterComponent } from './app-root/test-starter/test-starter.component';
 import { MonitorStarterComponent } from './app-root/monitor-starter/monitor-starter.component';
 import { PrivacyComponent } from './app-root/privacy/privacy.component';
+import { AlertModule } from './shared/alert/alert.module';
 
 @NgModule({
   declarations: [
@@ -76,7 +77,8 @@ import { PrivacyComponent } from './app-root/privacy/privacy.component';
     HttpClientModule,
     RouterModule,
     AppRoutingModule,
-    IqbComponentsModule.forRoot()
+    IqbComponentsModule.forRoot(),
+    AlertModule
   ],
   providers: [
     BackendService,