* Use a config struct when scanning and engine source.
* fix tests.
* Move test_helpers to the sources pkg.
* Handle ScanGit error in tests.
* adderss comments.
* Use functional options.
* Remove temp var.
* Add better var names for the setup functions for each config.
* Remove unused var.
* fix error logs.
* fix error logs.
* single line.
* remove blank lines.
* Refactor Engine to wait for workers in a Finish method
This should allow the engine to run multiple concurrent scans if
desired before shutting down.
Additionally, this commit refactors some of the printing logic to the
output package.
* Fix tests
