LP2012971 Item Alerts Not Editable

LP2012971 Item Alerts Not Editable

Release-notes: Fixes invocation of (Manage) Item Alerts dialog in Holdings Editor
Release-notes: Adds batch edit for Item Alerts in Holdings Editor. Alerts get grouped together for editing if they are mostly identical
Release-notes: Adds Manage Alerts button to Item Alerts dialog during alert display in Angular ("eg2") interfaces.
Release-notes: Fixes TypeError: defaults is null exception for missing Default Item Alert Type preference
Release-notes: Adds a Changes Pending indicator for Holdings Editor

Note that we do not address LP2044028 where multiple invocations of the
Item Alerts dialog in the Holdings Editor do not show pending changes
prior to a Save.

Example testing:

    In staff client with Concerto dataset,
    Cataloging -> Retrieve Bib Record By ID -> 1
    Holdings View -> Show Copies
    Select lines 5 and 6 (for CONC40000536 and CONC41000536)
    -> Edit: Edit Items
    -> Add Item Alerts: Item Alerts
    Should see a dialog for "Managing alerts in common for 2 item(s)."
    Normal Checkout, Test Note 123 -> Add New, Apply Changes
    Should see a CHanges Pending label before Apply All & Save
    Apply All, Save & Exit

    Back in Holdings View,
    Select lines 5 and 8 (for CONC40000536 and CONC4000036)
    -> Edit: Edit Items
    -> Add Item Alerts: Item Alerts
    Should see a dialog for "Managing alerts in common for 2 item(s)."
    Should not see the "Test Note 123" alert.
    Close tab

    Back in Holdings View,
    Select lines 5 and 6 again
    -> Edit: Edit Items
    -> Add Item Alerts: Item Alerts
    Should see a dialog for "Managing alerts in common for 2 item(s)."
    Should also see the "Test Note 123" alert.
    Close tab

    Circulation -> Check Out
    99999372363 -> Submit
    In the URL, change /eg/ to /eg2/ for the experimental Angular circ interface
    CONC40000536 -> Submit
    Should see the Item Alerts dialog with the Test Note 123 alert.
    Should also see a Manage Alerts button in the dialog.
    Manage Alerts
    Should see a new dialog, "Managing alerts for item CONC40000536",
    which is the same Item Alerts dialog from the Holdings Editor.
    Changes in this dialog are not reflected in the original Item Alerts
    dialog from which it was spawned.

Signed-off-by: Jason Etheridge <jason@equinoxoli.org>
Signed-off-by: Carol Witt <wittc@cwmars.org>
Signed-off-by: blake <blake@mobiusconsortium.org>
Signed-off-by: Steven Mayo <smayo@georgialibraries.org>
Signed-off-by: Jane Sandberg <js7389@princeton.edu>
Signed-off-by: Michele Morgan <mmorgan@noblenet.org>