title: Issue when model changes within AJAX call in ngx-admin
body: <p>I downloaded the latest build of ngx-admin (<a href="https://github.com/akveo/ngx-admin" rel="nofollow noreferrer">https://github.com/akveo/ngx-admin</a>), and served it up locally. In the <code>./@core/data/users.service.ts</code> file I have added the following method</p>
  
  <pre><code>  getHeroes (): Observable&lt;any[]&gt; {
      return this.http.get&lt;any[]&gt;('http://localhost:63468/api/clubs/heroes');
    }
  </code></pre>
  
  <p>That endpoint just returns some JSON like so:</p>
  
  <pre><code>[{"id":11,"name":"Mr. Nice"},{"id":12,"name":"Mr. Nice2"},{"id":13,"name":"Mr. Nice3"},{"id":14,"name":"Mr. Nice4"},{"id":15,"name":"Mr. Nice5"},{"id":16,"name":"Mr. Nice6"},{"id":17,"name":"Mr. Nice7"},{"id":18,"name":"Mr. Nice8"},{"id":19,"name":"Mr. Nice9"},{"id":20,"name":"Mr. Nice0"}]
  </code></pre>
  
  <p>In <code>./@theme/components/header/header.component.ts</code> I have added a click handler method:</p>
  
  <pre><code>  getHero() {
      this.userService.getHeroes()
        .subscribe(heroes =&gt; { 
          debugger;
          this.hero = heroes[0]
        });
    }
  </code></pre>
  
  <p>In <code>./@theme/components/header/header.component.html</code> I added a button and click event like:</p>
  
  <pre><code>  &lt;button (click)="getHero()"&gt;
      add hero
    &lt;/button&gt;
    {{hero?.name}}
  </code></pre>
  
  <p>I have done this to the same example project on Angular.io (<a href="https://angular.io/tutorial/toh-pt6" rel="nofollow noreferrer">https://angular.io/tutorial/toh-pt6</a>).</p>
  
  <p><strong>The issue is:</strong></p>
  
  <p>In the ngx-admin application, once that debugger line is hit, the <code>this.hero = heroes[0]</code> is properly set with the data I expect. Once the execution leaves that line of code, the view is not updated. If I inject <code>private ref: ChangeDetectorRef</code>, and call <code>this.ref.detectChanges();</code> immediately after <code>this.hero = heroes[0]</code>, then the view is properly updated. However, in the angular.io example of heroes, the view is properly updated within the context of the subscribe call. In that application no <code>this.ref.detectChanges();</code> is required.</p>
  
  <p>Is there something in the ngx-admin project that is messing up the Angular change detection?</p>