Azure: DocumentDB Mongo $group is not supported
<p>After migrating my Mongo app to DocumentDB on Azure the <code>$group</code> queries are no longer working and are throwing the following error:</p>

<pre><code>{ MongoError: '$group' is not supported',
  name: 'MongoError',
  message: '\'$group\' is not supported',
  _t: 'OKMongoResponse',
  ok: 0,
  code: 115,
  errmsg: '\'$group\' is not supported',
  '$err': '\'$group\' is not supported' }
</code></pre>

<p>Has anyone else encountered this before and may have any suggestions?</p>