title: How to round an int in Qt to the nearest 5
body: <p>I am looking for a good way to round an int in Qt to the nearest 5.</p>
  
  <p>e.g:</p>
  
  <pre><code>8 -&gt; 10  
  12 -&gt; 10  
  13 -&gt; 15  
  15 -&gt; 15  
  17 -&gt; 15
  </code></pre>
  
  <p>and so on</p>