feat(kzip): add source/input directories recursively (#4302)
feat(kzip): add source/input directories recursively (#4302)

* feat(kzip): add source/input directories recursively

* chore: address comments

kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe,kythe/kythe