Bug 15326: (follow-up) Fix staff permissions and consider library limits

Bug 15326: (follow-up) Fix staff permissions and consider library limits

To test:
1. Take note of what your logged in library is
2. Add a new page that can be viewed on the OPAC and staff interface.
Limit the library to a different library, not your logged in library
3. Use a News item to create a hyperlink to your new page on the OPAC
and staff interface.
4. Confirm that a page error shows if you try to view the new page.
5. Edit the new page and set the library to All libraries.
6. Try to go to the new page again and confirm it shows.
7. Log out and log back into the staff interface as a staff user that
isn't a superlibrarian
8. Confirm you can view the new page as this user

Sponsored-by: Horowhenua Libraries Trust
Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>