the text of a document after any and all changes are applied.
Changed the setDocumentValidator() to setDocumentHelpers() and allow
the specification of either a DocumentValidator, a DocumentTransformer, or
both.
git-svn-id: https://samskivert.googlecode.com/svn/trunk@801 6335cc39-0255-0410-8fd6-9bcaacd3b74c