https://github.com/munin-monitoring/contrib/issues/876
https://github.com/munin-monitoring/contrib/files/1797128/varnish5_.txt
my $configtype = $ASPECTS{$self}{'type'};
to
my $configtype = $ASPECTS{$self}{'type'} ? $ASPECTS{$self}{'type'} : '';
http://lab.geo.jp/blog/perl/use-of-uninitialized-value-in-string-eq.html
