A nice idea for a new Axmol UI class: ax::ui::Tree

[aismann]

Idea comes from Behavior Trees

Here a "very early" example: (Live::Editor for move events)

uiTree.mp4

uiTree2.mp4

Each node can have its own "image" so it will be look like the screenshot above.
Developer needs only define "image" and event/action.
The tree structure and size/position can be "selected" and ax::ui::tree make the rest (positioning all your nodes correct (structure/size/position)