* A root component with @DesignRoot must always use its superclass for
default values. Otherwise the written design will be empty as the
design is read in the constructor.
* A component which is not the root must not write its component tree
if the component tree is generated in the constructor. This is a
simplification which should be good enough for most cases (can't add
children in constructor and also using addComponent - in this case
the component added with addComponent will not be written).
* Test cases for nested templates
Change-Id: I3a384d1d8654b9865a3a790ebeb055a300a62135
* Rename VOrderedLayout to VAbstractOrderedLayout
* Move VAbstractOrderedLayout to the orderedlayout package
* Extract Slot to a standalone class with Icon as a private inner class
* Extract CaptionPosition to a standalone class
Change-Id: Id9450b30838a4511bd3c3b7cf371e145274ff198