Resizable description box on create new node window

[Steven-TB]

When selecting nodes from the "Create New Node" window, there is a description box at the bottom which displays instructions and useful information about the node. This window is fixed at 4 lines tall which makes reading the information quite difficult.

[Calinou]

This should be fairly easy by replacing the existing node structure within editor/create_dialog.cpp:

VBoxContainer
	Label ("Search:" text)
	LineEdit (search field)
	Label ("Matches:" text)
	Tree (results list)
	Label ("Description:" text)
	EditorHelpBit (description)

With:

VBoxContainer
	Label ("Search:" text)
	LineEdit (search field)
VSplitContainer
	VBoxContainer
		Label ("Matches:" text)
		Tree (results list)
	VBoxContainer
		Label ("Description:" text)
		EditorHelpBit (description)

I have a WIP branch but I didn't get it to work correctly yet: https://github.com/Calinou/godot/tree/editor-help-bit-allow-resize

[Calinou]

• Closing in favor of Editor: Make the description area in “Create New Node” dialog resizable #12517.