title: How to conditionally include code only if above certain iOS version?
body: <p>I have a piece of code that only works on iOS 6 or greater.</p>
  
  <pre><code>control.tintColor = [UIColor greenColor];
  </code></pre>
  
  <p>Is there a ready to use compiler directive like <code>#ifdef iOS6_or_greater</code>?</p>