Implement generic get dynamic fields lookup routines

- Tickets cannot be closed when an open ticket exists
- Tickets/Tasks cannot be closed when required for close fields are missing
data
- Add isCloseable routine to ticket/task classes

Fixes #2328

This patch shores up the new list management feature with the custom list
handler feature written to support lists being saved in a table other than
%list_item, namely the built-in ticket status list.

Also squelch the 'You sure?' popup appearing multiple times.

Restrict view access depending on agent's perm.

Also,
* use current year when no company name exists (yet)
* log a `created` timestamp for new files
* drop table %group during the upgrade

Also fix several javascript errors on ticket edit

The ORM should skip updates in the InstrumentedList for deleted items.

This allows messages to be stashed in the session and displayed on a
following request. This will be pivotal in implementing the PRG
(post-redirect-get).

* Make the "Items" tab the default
* Drop the "Showing ..." text and add a count to the items tab
* Redirect to "Items" tab when creating a new list
* Add a new list item by ajax rather than refresh