Added function to check if machine is part of a domain.

pkgtool.pm

@@ -20,6 +20,7 @@ require Exporter;
 
 use logging;
 use cfgparser;
+use sysinfo;
 
 use Symbol 'gensym';
 use Cwd;
@@ -601,6 +602,12 @@ sub get_default_dnsdomain ()
 	return $found;
 }
 
+sub is_part_of_domain ()
+{
+	my $wbem = get_wbem_info();
+	return defined $wbem && $$wbem{'PartOfDomain'};
+}
+
 sub get_registry_value ($)
 {
 	my ($node) = @_;