title: I can't do a request that needs to set a header with axios
body: <p>I'm trying to get some datas from an external API (from Mashape) that requires a specific header to set the API key.</p>
  
  <p>Everything is ok using jQuery :</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>$.ajax({
      url: 'https://omgvamp-hearthstone-v1.p.mashape.com/cardbacks',
      type: 'GET',
      data: {},
      dataType: 'json',
      success: function(data) { console.dir((data.source)); },
      error: function(err) { alert(err); },
      beforeSend: function(xhr) {
      xhr.setRequestHeader("X-Mashape-Authorization", "MY_API_KEY");
      }
  });</code></pre>
  </div>
  </div>
  </p>
  
  <p>However, when I'm trying to do the same request with axios for a react application, I have a 404 error:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>axios.get({
    url: 'https://omgvamp-hearthstone-v1.p.mashape.com/cardbacks',
    headers: {
        "X-Mashape-Authorization": "MY_API_KEY"
     }
   })</code></pre>
  </div>
  </div>
  </p>
  
  <p>Is there something I'm missing ? Thanks.</p>