title: Find <a> with only one img tag in it
body: <p>How would a regex look to find all <code>a</code> tags with only one <code>img</code> tag in it.</p>
  
  <p>this shows an example:
  <code>&lt;a href="somelink"&gt;&lt;img src="somelink" border="0"/&gt;&lt;/a&gt;</code></p>
  
  <p>It should also match if a linebreak occurs between the <code>img</code> tag and the <code>a</code> tag.</p>
  
  <p>thanks for your help </p>