CLI script to remove thumbnails and file versioning

Hi,

It's very nice, to add script such as empty_trash.php

- to remove all previous version of thumbnails

- to remove file version based on parameter such as date or number (for exemple

remove all file version previous 2015-01 or only to keep last 3 version even if filerun

is configured to keep 7 version.

When we have very large file storage, it is safer to run a script.

Thank