title: Filter JS multidimensional array
body: <p>I am attempting to filter some events and their corresponding time slots. The data structure is like so:</p>
  
  <pre><code>var items = [
    {
      title: 'Category Title',
      events: [
        {
          title : '1:00pm',
          category : 1
        },
        {
          title: '2:00pm',
          category : 2
        }
      ]
    },
    {
      title: 'Category Title 2',
      events: [
        {
          title : '3:00pm',
          category : 1
        },
        {
          title: '4:00pm',
          category : 2
        }
      ]
    }
  ];
  </code></pre>
  
  <p>I am wanting to filter events by their category. I've tried using filters/maps but can't seem to figure it out. For example, how would I filter the list to only return items with the category of 1?</p>