Add -by-repo for a detailed per repo breakdown

Changelog for v0.0.9:

Commits
873a22b Update README about -by-repo flag by @alexellis
f7fe048 Add repo-level breakdowns by @alexellis
80587e2 Update README.md by @alexellis
731b5b6 Update README.md by @alexellis

Changes: v0.0.8...v0.0.9

Generated by Derek