Bug 8895 - Warning in systempreferences.pl: Use of uninitialized value in length...

Bug 8895 - Warning in systempreferences.pl: Use of uninitialized value in length...

Clicking on Local use tab in system preferences results in warning in log file:

systempreferences.pl: Use of uninitialized value in length at (...)/admin/systempreferences.pl line 456

Reason: content field "value" in table "systempreferences" can be NULL (and is tested for length).

Added test for "defined" at to places.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>