FEAT #8758 add logout

src/frontend/app/sidebar/sidebar.component.html

 <nav class="sidebar" *ngIf="snavLeftComponent.opened">
   <div class="main-header">
     <header class="profile-header">
-        <button class="logout-button" mat-icon-button routerLink="/login">
+        <button class="logout-button" mat-icon-button (click)="logout()">
             <mat-icon  fontSet="fas" fontIcon="fa-sign-out-alt"></mat-icon>
         </button>
       <div class="user">

src/frontend/app/sidebar/sidebar.component.ts

@@ -78,4 +78,13 @@ export class SidebarComponent implements OnInit, AfterViewInit {
     this.snavLeftComponent.close();
     this.snavRightComponent.open();
   }
+
+  logout() {
+    this.http.get('../rest/logout')
+      .subscribe((data: any) => {
+        this.router.navigate(['/login']);
+      }, (err: any) => {
+          this.notificationService.handleErrors(err);
+      });
+  }
 }