title: Remove all event listeners of a Backbone view
body: <p>Is there a way to remove all event listens instantiated by a backbone view? For example, suppose I have the following HTML/JavaScript. When #box is clicked, I want a pop-up to say hello.</p>
  
  <pre><code>&lt;div id="box" style="height: 100px; width: 100px; background-color: red"&gt;&lt;/div&gt;
  
  var Listener = Backbone.View.extend({
      el: "#box",
      events:  {
          'click #box' : 'hello'
      },
      hello: function () {
          alert('hello!');
      }
  })
  
  var listener = new Listener();
  </code></pre>
  
  <p>Now, I want to remove the event listener. Setting listener to something else doesn't work:</p>
  
  <pre><code>listener = ''; // doesn't work
  </code></pre>
  
  <p>How do I remove the event listener?</p>