Bug 26346: Add option to make public lists editable by all staff

Bug 26346: Add option to make public lists editable by all staff

If a staff member has access to the staff client (either because
'catalogue' permission is enabled or they're a superlibrarian
then that user can add items (from OPAC or staff client) to a list
marked 'Staff only'

Test plan:
1. In the staff client go to: Lists > 'New list'. Notice under 'Allow changes to contents
from' there are three options: Nobody, Owner only, Anyone seeing this
list

2. Apply first 3 patches and run updatedatabase.pl
cd installer/data/mysql
sudo koha-shell <instance>
./updatedatabase.pl

3. Restart memcached and plack

4. Create 4 patron accounts:
- User A : Superlibrarian permissions
- User B : 'Staff access, allows viewing of catalogue in staff interface
(catalogue)'
- User C : No permissions
- User D : 'Staff access, allows viewing of catalogue in staff
interface' and 'Lists' > Edit public lists (edit_public_lists)' sub-permission

5. Login to staff client as User A.
Create a public list and select the new 'Staff only' option under 'Allow changes to contents from'

6. Log into the staff client as User B.
Confirm you can add items to the list from the following staff client pages:
- Individual list page using the 'Add items' button
- Staff client search result page
- Staff client biblio detail page

7. Confirm you can remove items from the list

8. Confirm you can perform an OPAC search when not logged in

9. Log into the OPAC as User B. Confirm you can add items to the list
from the following OPAC pages:
- OPAC search result page
- OPAC biblio detail page

10. Log into the OPAC as User C. Do an OPAC search and confirm you
can view the list, but not add items to it

11. Login to the staff client as User B. Create a new list with the
following settings:
- 'Category'='Private',
- 'Allow changes to contents from'='Staff only'

Notice a red hint message is displayed.
Change 'Category'='Public' and notice the hint is removed

12. Log into the OPAC as User C. Notice the 'Staff only' option is not
available when creating a list

13. Log into the OPAC as User B. Repeat step 11. Confirm the same
outcome

14. Log into the staff client as User A. Create a list with the
following settings:

- Public = 'Public'
- Allow changes to contents from = 'owner only'

15. Log into the staff client as User D. Edit the list from step 14
confirm you can edit the list to have 'Allow changes to contents from' =
'Staff only'

16. Run Patron.t and Virtualshelves.t unit tests:
sudo koha-shell <instance>
prove t/db_dependent/Koha/Patron.t
prove t/db_dependent/Virtualshelves.t

Sponsored-by: Horowhenua District Council, New Zealand
Signed-off-by: Andrew Fuerste-Henry <andrew@bywatersolutions.com>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>