* allow float for API delay in seconds, and document default is 0 ([560668d](https://gitlab.com/to-be-continuous/tools/gitlab-butler/commit/560668d9527e16f30fbdcbf1bdfae4e1e287a1f5))
* only visit each subgroup once (+ order by path) ([5485c2b](https://gitlab.com/to-be-continuous/tools/gitlab-butler/commit/5485c2bf6b57f0f45a2301a29843fda8aecfb63c))
* set a specific user-agent (gitlab-butler/VERSION) ([fd7b690](https://gitlab.com/to-be-continuous/tools/gitlab-butler/commit/fd7b6901e74fba3aacd285d48d46469de8ed93b8))
### Features
***cli:** improve output (count of deleted pipelines per project) ([6300284](https://gitlab.com/to-be-continuous/tools/gitlab-butler/commit/6300284d7bab5503c61a3004666d7b94e24e6c29))