restricted zapp brannigan goodie to m/quote/

lib/DDG/Goodie/ZappBrannigan.pm

@@ -7,6 +7,7 @@ triggers any => "zapp", "brannigan";
 zci is_cached => 0;
 
 handle query => sub {
+    return if $_ !~ m/quote/;
     my @quotes = share('quotes.txt')->slurp;
     my $rand = int(rand(scalar(@quotes)));
     my $quote = $quotes[$rand];