title: Remove an item in Firebase
body: <p>I'm using AngularFire but if the solution is in the way of pure JavaScript it will be welcome.</p>
  
  <p>I have a Firebase Collection similar to this:</p>
  
  <pre><code>productExample: {
      name: 'Motorbike',
      category: 'Cross',
      images: {
          0: 'image1.jpg',
          1: 'image2.jpg',
          2: 'image3.jpg'
      } 
  }
  </code></pre>
  
  <p>I want to remove the image1.jpg. ¿How can I do it? I've tried so many things but I have not got the solution. Thanks for the help!</p>