support comment in the pkglist on debian/ubuntu

git-svn-id: https://svn.code.sf.net/p/xcat/code/xcat-core/trunk@15513 8638fb3e-16cb-4fca-ae20-7b5d299a9bcd

xCAT-server/lib/perl/xCAT/Template.pm

@@ -158,6 +158,9 @@ sub subvars {
         # append preseed directive lines
         while (<PKGLISTFILE>) {
           chomp $_;
+          if (/^\s*#.*/ ){
+            next;
+          }
           $pkglist .= " " . $_;
         }