bug 10865: (follow-up) allow patrons to make their public lists private when OpacAllo...

bug 10865: (follow-up) allow patrons to make their public lists private when OpacAllowPublicListCreation is off

This patch ensures that patrons continue to have the ability to make
their public lists private for any public lists they control that were
created before the library turned the OpacAllowPublicListCreation
system preference off.

To test:

[1] Ensure OpacAllowPublicListCreation is on.
[2] As a patron, create a public list in the OPAC.  Also, create
    a private list.
[3] Turn OpacAllowPublicListCreation off.
[4] Back in the OPAC, verify that the public list can be edited
    and that there are drop-downs for category and permissions.
    Also verify that there is a warning that the patron cannot
    change it back if they convert a public list to private.
[5] Edit the private list created in step 2.  Verify that the
    category and permissions drop-downs are not displayed.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Broust <jean-manuel.broust@univ-lyon2.fr>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 7dd0e9a41fd639e86ed32d98d863d605a6ba63e8)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>