tornadofx.javafx.scene.control.TreeItem

collapseAll	`fun <T> TreeItem<T>.collapseAll(): Unit` Collapse this TreeItem and all its children.
expandAll	`fun <T> TreeItem<T>.expandAll(): Unit` Expand this `TreeItem and all its children.
expandTo	`fun <T> TreeItem<T>.expandTo(depth: Int): Unit` Expand this TreeItem and children down to `depth`.
plusAssign	`operator fun <T> TreeItem<T>.plusAssign(treeItem: TreeItem<T>): Unit`
treeitem	`fun <T> TreeItem<T>.treeitem(value: T? = null, op: TreeItem<T>.() -> Unit = {}): TreeItem<T>`