title: Member of In queryBuilder
body: <p>I need to request some users by groups list. For this I must use "Member of" function same described here : <a href="http://docs.doctrine-project.org/en/2.0.x/reference/dql-doctrine-query-language.html" rel="nofollow">http://docs.doctrine-project.org/en/2.0.x/reference/dql-doctrine-query-language.html</a></p>
  
  <p>But in my projet, i prefer use doctrine queryBuilder (documented here : <a href="http://docs.doctrine-project.org/en/2.0.x/reference/query-builder.html" rel="nofollow">http://docs.doctrine-project.org/en/2.0.x/reference/query-builder.html</a>) but i doesn't found any equivalent in query builder for the "Member of" DQL syntax.</p>
  
  <p>Any idea ?</p>