org            string
	ipAddresses    []net.IP
	dnsNames       []string
	emailAddresses []string
	uris           []string
}

// overlayPEMOptions overlays one set of pemOptions on top of another to allow
// for easily overriding a single field in the options
func overlayPEMOptions(opts ...pemOptions) pemOptions {
	if len(opts) == 0 {
		return pemOptions{}
	}
	base := opts[0]
	for _, opt := range opts[1:] {