title: Convert ints to booleans
body: <p>Is there a way that I can convert int/short values to booleans? I'm receiving JSON that looks like this:</p>
  
  <pre><code>{ is_user: "0", is_guest: "0" }
  </code></pre>
  
  <p>I'm trying to serialize it into a type that looks like this:</p>
  
  <pre><code>class UserInfo {
  
      @SerializedName("is_user")
      private boolean isUser;
  
      @SerializedName("is_guest")
      private boolean isGuest;
  
      /* ... */
  }
  </code></pre>
  
  <p>How can I make Gson translate these int/short fields into booleans?</p>