title: PrimeNg DropDown - User can't clear the value
body: <p>I'm implementing primeNg dropdown component in my Angular2 application.</p>
  
  <pre><code>&lt;p-dropdown [options]="listCustomers_itm" placeholder="Selezionare" [(ngModel)]="Customer_itm" [ngModelOptions]="{standalone: true}" [style]="{'width':'225px'}" filter="filter"  (onChange)="onCustomerSelect($event.value)"&gt;
  &lt;/p-dropdown&gt;
  </code></pre>
  
  <p>All works fine except one annoing thing:</p>
  
  <p>Once time the user has selected an option, <strong>he can't clear the selected value</strong>...</p>
  
  <p>Can you help me?</p>