[2.0.4] Validate both 'class' and 'value' is not set on a group.
[2.0.4] Validate both 'class' and 'value' is not set on a group.

git-svn-id: cdbd3c3453b226d8644b39c93ea790e37ea3ca1b@166 fa12aebc-18e6-4bd0-a00b-c41c8e91b89f

beanio/beanio,beanio/beanio