4c22f122e1
Layout properties work similarly to child properties, with the added headache that they require the 3-tuple: ( layout manager, container, actor ) to be valid in order to be inspected, parsed and applied. This means using the newly added back-pointer from the container to the layout manager and then rejigging a bit how the ScriptParser handles the unresolved properties. Similarly to the child properties, which use the "child::" prefix, the layout manager properties use the "layout::" prefix and are defined with the child of a container holding a layout manager.