LBase: added writeOnly sugar
implemented findParentComponentOfClass, getParentComponent, moved startDragging from LJComponent to LComponent and added a lua dedicated method acting as a dynamic_cast, named as
LListBox: added shortcut multipleSelectionEnabled
LTreeViewItem: made boolean optional for getItemPosition
LTreeViewItem: shortcuts for itemHeight and itemPosition
LTreeViewItem: can call getDragSourceDescription without a callback
LuaO: commented out stacktrace function, not used at the moment
lua/LClass: commented out extra debug messages