River score of packages

[tchoutri]

Mandatory read: https://neilb.org/2015/04/20/river-of-cpan.html

• We want to know how many dependents (direct and transitive) packages have

• We want to establish river stages that will be brackets of dependents, for instance:

Stage 6	Stage 5	Stage 4	Stage 3	Stage 2	Stage 1
10k+	1k - 9999	100 - 999	10 - 99	1 - 9	0