Destroys all but the most recent version(s) for items on a given date (or
on all dates). Useful for deleting drafts.
Options:
- :keeping - An `integer` indicating the number of versions to be kept for
each item per date. Defaults to `1`.
- :date - Should either be a `Date` object specifying which date to destroy
versions for or `:all`, which will specify that all dates should be
cleaned. Defaults to `:all`.
- :item_id - The `id` for the item to be cleaned on, or `nil`, which causes
all items to be cleaned. Defaults to `nil`.