title: Add placeholder to select tag in angular2
body: <p>I have simple component that contains only form:</p>
  
  <pre><code>import {Component, FORM_DIRECTIVES, NgFor} from 'angular2/angular2';
  
  
  @Component({
    selector: 'test-component',
    directives: [FORM_DIRECTIVES, NgFor],
    template: `
      &lt;form class="form-inline" (ng-submit)="onSubmit()" #form="form"&gt;
        &lt;div class="form-group"&gt;
          &lt;select class="form-control" 
            [(ng-model)]="model.server" 
            ng-control="server" 
            #server="form" 
            required&gt;
            &lt;option selected hidden&gt;placeholder&lt;/option&gt;
            &lt;option *ng-for="#server of servers" 
              [value]="server"&gt;{{ server | uppercase }}
            &lt;/option&gt;
          &lt;/select&gt;
        &lt;/div&gt;
        &lt;div class="form-group"&gt;
          &lt;input class="btn btn-primary" type="submit" value="Load"
            [disabled]="!form.form.valid"&gt;
        &lt;/div&gt;
      &lt;/form&gt;
    `
  })
  export class TestComponent {
    public model: Model = new Model();
    public servers: string[] = ['a', 'b', 'c'];
  
    onSubmit(): void {
      // Complicated logic.
  
      // Reset form.
      this.model.reset();
    }
  }
  
  class Model {
    constructor(
      public server: string = ''
    ) { }
  
    reset(): void {
      this.server = '';
    }
  }
  </code></pre>
  
  <p>I want to create "placeholder" for my select, however ng-model overrides selected property which cause no selected option at all. Any sugestions? I am using angular 2.0.0-alpha.48.</p>