Remove name attribute radio inputs inside cloned nodes by dd-proxy (Fix #1663)

This is a possible fix for https://github.com/yui/yui3/issues/1663.

When cloning a node, removing the `name` attribute from any inputs of type radio inside the dragged node, will prevent them from unchecking the selected radio button on its group.

I've added a test to verify this. Somehow it works properly when launched with yeti, but fails to pass when launched via yogi. Am I missing something here?

I've also created a demo [with the working fix](http://jsfiddle.net/jbalsas/9KGL7/)