title: Spotify API - autocomplete search results are null
body: <p>Playing with Spotify API - I would like to use jQuery to autocomplete a field with artists as I type. So far I'm working with the following:</p>
  
  <p>HTML:</p>
  
  <pre><code>&lt;input type="text" class="text-box" placeholder="Enter Artist" id="artist-input"&gt; 
  </code></pre>
  
  <p>Javascript:</p>
  
  <pre><code>$(document).ready(function() {
  
    $("#artist-input").autocomplete({
      source: function(request, response) {
          $.ajax({
              type: "GET",
              url: "https://api.spotify.com/v1/search",
              dataType: "json",
              data: {
                  type: "artist",
                  limit: 3,
                  contentType: "application/json; charset=utf-8",
                  format: "json",
                  q: request.term
              },
              success: function(data) {
                  response($.map(data.artists, function(item) {
                      return {
                          label: item.name,
                          value: item.name,
                          id: item.id
                      }
                  }));
              }
          });
      },
      minLength: 3,
      select: function(event, ui) {
          $("#artist-input").val(ui.item.value);
          window.location.href = "#" + ui.item.value;
      },
  });
  
  });
  </code></pre>
  
  <p>Running this, results:</p>
  
  <pre><code>functions.js:35 Uncaught TypeError: Cannot read property 'name' of null
  </code></pre>
  
  <p>So my question is do I need to do some sort of authentication before this process can run? My thought process is that it's making the call but it's returning as null, and I'm missing an extra step...</p>
  
  <p>Here is a codepen with this example: <a href="http://codepen.io/anon/pen/PGKLpj" rel="nofollow">http://codepen.io/anon/pen/PGKLpj</a></p>