Boxes + horizontal flow makes for more readable call graphs

[DanielVF]

This is my personal set of modifications to the call graph generation. Putting them here to see if anyone else likes them.

Boxes vs ellipses

By having nodes be boxes instead of ellipses, the information packs down so much denser. The "circle" style wastes huge amounts of space on either side. This change is an easy win.

Horizontal flow vs vertical.

This one is more opinionated. When there are more than five or so elements in a given layer, horizontal flow allows much more to be onscreen at once, since the nodes stack short side to short side. Since almost everything I do is looking at full contracts with this tool, this works out much better for me. Vertical ranking means that even on a widescreen monitor, I can't see the whole contract.

Using vertical ranking. (Old, but with boxes)

Using horizontal. (After)

[CLAassistant]

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