Simple refresh for async TreeView

[fhayd]

Hello, it's me again :)

We ran on a probleme where we have to refresh the root component of the Treeview. Because it is a one time initialization on OnInitializedAsync(), it is not possible to simply do so right now. I just add a public Refresh method on the TreeViewAsync, that simply call OnInitializedAsync() on the root node. This re-initialize the entire TreeView.

Once again I am open to any suggestion or correction, do not hesitate :)

[fhayd]

To answer your last question about the difference between sync and async, the sync TreeView as a list of Items as parameters that can be changed.

I will made the corrections