title: ng-pattern to allow alpha and certain special characters
body: <p>In form - name field I want to do a validation against</p>
  
  <ul>
  <li>Should allow only Alpha characters</li>
  <li>Allow space</li>
  <li>Allow certain special characters - <code>_ \ / - . ’</code></li>
  </ul>
  
  <p>I tried,</p>
  
  <pre><code> ng-pattern="/^[a-z]+[_+\+/+-+.+’][a-z]*$/"
  </code></pre>
  
  <p>Looks like I have missed out something as its not working!</p>