title: Decode case class, String or Int in circe
body: <p>I use some Rest API responding with json containing a sort of "mixed" field. By mixed I mean that it can take values of a different type. In my case <code>Object</code>, <code>String</code> and <code>Int</code> are allowed. The <code>Object</code> itself consists of 1 <code>Int</code> and 1 <code>String</code>.</p>
  
  <p>The object I need to decode looks as:</p>
  
  <p>I</p>
  
  <pre><code>{
     field1: 32,
     ...
     value: {
        id: 23,
        text: "text"
     }
  }
  </code></pre>
  
  <p>II</p>
  
  <pre><code>{
     field1: 32,
     ...
     value: 21
  }
  </code></pre>
  
  <p>III</p>
  
  <pre><code>{
     field1: 32,
     ...
     value: "value"
  }
  </code></pre>
  
  <p>How to deal with such objects in circe?</p>