title: Header Content Type in axios can't set application/json
body: <p>I am trying to configure headers in a project with <code>vue.js</code> and <code>axios</code> to call a service that expects a json. My problem is that when I make my call with the <code>POST</code> method, <code>axios</code> puts to the request <code>Content-Type</code> header with <code>x-www-urlencoded</code>, but in my code, I put manually <code>Content-Type</code> header with <code>application / json</code>.</p>
  
  <pre><code>var loginObj = {
      var1: payload.login,
      var2: payload.password
  }
  
  const jsonLogin = JSON.stringify(loginObj)
  
  const config = {
      headers: {
        'content-type': 'application/json',
        'Accept': 'application/json'
      }
  }
  
  axios({
      url: 'url/example',
      method: 'post',
      data: jsonLogin,
      config
  })
  .then(response =&gt; {
      console.log(response);
  })
  .catch(error =&gt; {
      console.log(error);
  })
  </code></pre>