GitLab

- Null pointer error fixed
- Additional features were added:
-- debug: runs in debug mode
-- latest: sets the number of latest tags not to delete
-- repo: match by repository name (regexp)
-- tag: match by tag name (regexp)

NOTE: This pull request has been submitted by @marcuslinke

- Only for insecure registries
- Can filter images by age (year, month, day, or any combination)