title: batch update in play-morphia
body: <p>I'm using Play framework 1.2.5 and Play-Morphia module.
  I want to know if there's a way to update many objects at one Morphia query. I've found this example at <a href="https://github.com/greenlaw110/play-morphia/blob/master/documentation/manual/crud.textile" rel="nofollow">https://github.com/greenlaw110/play-morphia/blob/master/documentation/manual/crud.textile</a>, but it seems that I can't use "in" operation in norder to find all the objects which I hold in a list of their IDs.</p>
  
  <p>I'm trying to update the paidInvoiceDocNum filed in each of the objects which their IDs are in the list "itemsIds". This is what I've tried so far:
  String q = TransactionItem.find().field("id").in(itemsIds).toString();
  TransactionItem.o().set("paidInvoiceDocNum", String.valueOf(docNumber)).update(q);</p>
  
  <p>Without the .toString() it doesn't work either.
  Any suggestions?</p>