Bug 10240: (follow-up) warn when patron's card is expired

Bug 10240: (follow-up) warn when patron's card is expired

This patch improves the alert messages to be slightly better English
and warns the librarian if a patron's card has expired. Like all alerts,
this is non-fatal since in the case of network failure there is no
particular reason to expect that the offline database is current.
To test this particular patch you can try checking something out to an
expired patron, otherwise test plan remains the same as above.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>