title: Spring creates wrong db query (Basic call with example)
body: <p>I'm using Spring and Mongo and the regex query is not correct somehow...</p>
  <pre><code>String text = &quot;test&quot;;
  ...
  criteria.and(&quot;title&quot;).regex(text, &quot;i&quot;);
  Query.query(criteria); // Output bellow
  </code></pre>
  <p>Create this query:</p>
  <pre><code> {&quot;title&quot;:{
        &quot;$regularExpression&quot;:{
           &quot;pattern&quot;:&quot;test&quot;,
           &quot;options&quot;:&quot;i&quot;
        }
     }}
  </code></pre>
  <p>Instead of:</p>
  <pre><code>{
    &quot;title&quot;:{
       &quot;$regex&quot;:&quot;test&quot;,
       &quot;$options&quot;:&quot;i&quot;
  }}
  </code></pre>
  <p><strong>ERROR: unknown operator: $regularExpression</strong></p>