title: Remove leading and trailing newline characters from NSString
body: <p>I have an <code>NSString</code> which consists of the text a user has entered into a <code>UITextView</code>. As a result, the string may have leading and trailing newline characters, along with newline characters within the string (if they hit the Return key to type on a new line). I would like to remove any newline characters from the beginning and end of the string, leaving any within the string intact.</p>
  
  <p>What would be the best way to go about this?</p>