Bug 11897: Stockrotation

Bug 11897: Stockrotation

The stock rotation feature adds a batch process to automate rotation of
catalgue items with a staff client page under tools to manage rotas/schedules.

Once a rota is configured, and your staff user has the right permissions
to allocate items, then an additional tab will appear on biblio records
allowing the management of of which rota, if any, individual items belong to.

It also includes a cron script to process the items on a daily basis.

Signed-off-by: Kathleen Milne <kathleen.milne@cne-siar.gov.uk>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Edit: I removed a temporary file

Signed-off-by: Nick Clemens <nick@bywatersolutions.com>