title: Remove beginning and trailing new line characters from NSString
body: <p>How can one remove <strong>only</strong> the beginning and trailing new line <strong>\n</strong> from a NSString.</p>
  
  <p>For e.g.</p>
  
  <pre><code>@"\n\n\n\Hi\nHow are you\nToday.\n\n\n\n"
  </code></pre>
  
  <p>output:</p>
  
  <pre><code>@"Hi\nHow are you\nToday."
  </code></pre>
  
  <p>Thanks.</p>