title: Sort a collection in grails by date
body: <p>I am wanting to sort a collection in grails by date I am currently doing the following:</p>
  
  <pre><code>def pics = Picture.findAllByChild(child, [sort: 'dateCreated', order: 'desc'])
  pics.add(Post.findAllByPostedToAll(true))
  </code></pre>
  
  <p>Because I have added more items to the list i need to sort again by dateCreated descending
  It doesn't look like the sort class can do this.
  I have tried:</p>
  
  <pre><code>pics.sort(it.dateCreated)
  </code></pre>
  
  <p>But this is not allowed</p>