Koha::Logger
    use Koha::Logger;
    my $logger = Koha::Logger->get;
    $logger->warn( 'WARNING: Serious error encountered' );
    $logger->debug( 'I thought that this code was not used' );
    Returns a logger object (based on log4perl).
    Category and interface hash parameter are optional.
    Normally, the category should follow the current package and the interface
    should be set correctly via C4::Context.
    In order to prevent a crash when log4perl cannot write to Koha logfile,
    we check first before calling log4perl.
    If log4perl would add such a check, this would no longer be needed.
Dummy destroy to prevent call to AUTOLOAD
Kyle M Hall, <kyle@bywatersolutions.com> Marcel de Rooy, Rijksmuseum