UI add more layouting options

[Skytrias]

Currently we have V/H Stack style layouting similar to what a lot of retained mode UIs do. We also have "float" based positioning where you can specify a oc_vec2 target Position for a box.

In my opinion there should at least be another option to add "Absolute" layouting which always start at x=0, y=0 for things that should stick to the screen. Maybe this could be done with another style option, floatAbsolute=true?

Or we change names instead of oc_vec2 floatTarget we could have oc_vec2 absoluteTarget and oc_vec2 relativeTarget.

One other thing that was discussed in meetings was how a user could add custom lay outing options like Rect-Cut lay outing or anything more specialized.