Type aware layering of values displayed in highlight execution mode

[Quiztus2]

The layering of values shown during highlight execution mode should take the data type into account. I suggest moving types whose values do not change—such as refnum or lvclass—to the back of the display stack. This should also apply to ordinary VIs, similar to how property nodes are already handled. Otherwise values worth to know are hidden by actually useless info.

[raphschru]

I like the idea of making the debug values more readable, but I'd prefer a more general solution that makes all values readable.

Example:

Specifically in case where output terminals of a node are very close together, the font size of the debug labels could also be slightly reduced to make the group more vertically compact.