[core] Rename attachChildToLayout() to simply layoutChild()
[core] Rename detachChildFromLayout() to simply detachChild()
[core] Remove unnecessary position argument from TWLayoutManager API
[core] Rename getOuter*Edge() API to getLayout*()
[core] Remove 'edge' suffix from a few method names
[core] Rename 'edge' argument to 'limit' in canAddMoreViews()
[core] Consolidate/fix decorated left/top/right/bottom getters
[core] Move abstract method below start/end methods
[layouts] Remove vertical/horizontal spacing attributes

They should be implemented as item decorations now.