Allow the label of a property to be rendered as HTML. Also, allow the label of boolean panels to be rendered on the right hand side.

Suggested syntax is:

@PropertyLayout(
  named="Accept <a href="http://foo.org/terms">terms</a>?",
  namedEscaped=false
  labelPosition=LabelPosition.RIGHT
)

The Javadoc should state that LabelPosition.RIGHT is only supported by boolean panels; if specified for other panels it will be ignored and default to LEFT instead.