Bug 34597: (follow-up) Update system preference description and order of options

Bug 34597: (follow-up) Update system preference description and order of options

Update the note for the BlockExpiredPatronOpacActions system preference to
make it clearer, and to follow the standard convention for notes.

Order of options for 'Block expired patron OPAC actions' when editing the
patron category changed to alpabetical order, to match the system preference
order.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>