LP1735566: Ask before deleting items in non-ideal statuses in AngularJS

LP1735566: Ask before deleting items in non-ideal statuses in AngularJS

To test:

1) Apply this commit.
2) Log in as a user with COPY_DELETE_WARNING.override permission.
3) Go to item status and scan an item in a non-ideal status (like #1:
checked out)
4) Delete the item.  Note that you are alerted of the item's non-ideal
status, and you can confirm that you actually want to delete it.
5) Repeat steps 3-4 with an item in an ideal status (like #0:
Available). Note that no such alert appears.
6) Open the holdings view and repeat steps 4-5.
7) Log in as a user without the COPY_DELETE_WARNING.override
permission. Note that you are still informed about the non-ideal status,
but you aren't able to continue with the deletion without an admin
using their credentials.

Signed-off-by: Jane Sandberg <sandbej@linnbenton.edu>