add i18n for menu title

Author: WeihanLi

src/app/app.component.html

@@ -12,7 +12,7 @@
       <button mat-button class="app-menu-button" (click)="sidenav.toggle()">
         <i class="material-icons">menu</i>
       </button>
-      <span class="title" routerLink="/">{{title}}</span>
+      <span class="title" routerLink="/" i18n>{{title}}</span>
     </mat-toolbar>
   </header>
   <section class="app-content" style="margin: 58px auto 0;max-width:1280px;">