Fix graphs with gaps from tomcat_threads

My tomcat_threads graphs are missing some values, there are gaps. 
Actually when the value of currentThreadsBusy is "0", the plugin gives "U" and that creates the gaps
Someone proposed me a fix and it's working fine with the solution. See here : https://serverfault.com/questions/1003501/munin-graph-is-incomplete-with-tomcat-threads-plugin/1028741#1028741

plugins/node.d/tomcat_threads

@@ -129,7 +129,7 @@ if(exists $ARGV[0] and $ARGV[0] eq "config") {
 } else {
     for my $connector (@connectors) {
         my $clean = clean_fieldname($connector);
-        if(exists $xml->{'connector'}->{$connector}->{'threadInfo'}->[0]->{'currentThreadsBusy'} &&
+        if(exists $xml->{'connector'}->{$connector}->{'threadInfo'}->[0]->{'currentThreadsBusy'} ||
             exists $xml->{'connector'}->{$connector}->{'threadInfo'}->[0]->{'currentThreadCount'}) {
             print "${clean}_busy.value " . $xml->{'connector'}->{$connector}->{'threadInfo'}->[0]->{'currentThreadsBusy'} . "\n";
             print "${clean}_idle.value " .