tests/test-debugindexdot.out

diffstat: scale adds/removes proportionally to graph width

The previous method of scaling had a tendency to include graph lines that
went past the output width when the file with the most changes had a very
large number of changes.

created new head
digraph G {
	-1 -> 0
	0 -> 1
	0 -> 2
	2 -> 3
	1 -> 3
}