NodeModel should not implement TreeNode
remove duplicate method getParent(), keep getParentNode()
encapsulate internal field accesses
extract class SharedNodeData
refactoring: rename and move methods
constructor refactoring + node has its own extension container
fix text and user object handling
refactor: use static methods of NodeLinks for all accesses to NodeLinks object
do not share NodeLinks
clone action
fire node change events for all clones
nodeWriter
NodeBuilder for clones
remove unused methods
DetachedNodeList
delete operation for clones
add operation for clones
insert node actions support clones
refactor move nodes in direction, let is use moveNode(...) instead of its own actor
refactor insertNewNode