feature request: allow user to supply multiple directories

[sudolibre]

The user can currently supply a single directory that is ultimately passed as paths to git log to scope down which commits are analyzed. Git log can support multiple paths which comes in handy in some monorepo scenarios (e.g. git log HEAD -- go.mod cmd/app1 internal/app1). This request is to update svu to allow the user to pass in multiple "directories".