Add log rotation (#6564)

* Use flexi_logger; Add log rotation

* Add default rotation; Add FlexiLogger error

* Fix compilation error

* Remove logging to stdout if it's not a tty

* Fix formatting

Co-authored-by: Kian Paimani <[email protected]>

* Remove needless debug statement

* Default to unlimited size for log rotation

* Add more comments about log-age option

* Remove unused variable

* Fix typo in comment

Co-authored-by: Kian Paimani <[email protected]>