title: Make ReflectionToStringBuilder skip fields with null values
body: <p>I have to print object values in log file. I used:</p>
  
  <pre><code>ReflectionToStringBuilder.toString(this, ToStringStyle.MULTI_LINE_STYLE, true, true);
  </code></pre>
  
  <p>But it also prints null values which I don't want to include, for instance:</p>
  
  <blockquote>
    <p>Pojo@117d9a3[id=1,<strong>name=null</strong>,description=Manchester United,KEY=APP-KEY,secretKey=Alex ]</p>
  </blockquote>
  
  <p>How to suppress null values from being included?</p>