title: How to highlight multiple selections?
body: <p>For example I have some text in ace-editor and a list of ranges of rows and lines in text where highlightings should happened. Like this (they're bolded):</p>
  
  <p><em>Lorem ipsum dolor sit <strong>amet</strong>, consectetuer adipiscing elit. Nam cursus. 
  Morbi ut mi. Nullam enim leo, egestas id, <strong>condimentum</strong> at, laoreet mattis, 
  massa. Sed <strong>eleifend</strong> nonummy diam. Praesent mauris ante, elementum et, 
  bibendum at, <strong>posuere</strong> sit amet, nibh.</em></p>
  
  <p>How to highlight these words by using ace-editor API?</p>
  
  <p>How to highlight multiple lines?</p>