title: replace \t\t characters with <br> character rails
body: <p>I am making a parser of some website. 
  As an output from parser I get string like:</p>
  
  <pre><code>"some text \t\t some another text \t\t another text"
  </code></pre>
  
  <p>I want to replace <code>\t\t</code> with <code>&lt;br&gt;</code>.  How can I do this?</p>