* Add new module "mail_cleanup" in order to move/mark as read old messages
* Use correct Model + remove unnecessary conditions/assignments
* Add purging mechanism + cleanup is by default inactive
* Add new field + new info in README
* Correct type for purge_days + better checks
* Place expunge() call after parsing all messages
* Migration to 9.0 of mail_cleanup
* Fix README.rst
* Add __init__.py
* Fix error with multi mail servers
* Correct syntax for methods + use datetime.date.today