#!/usr/bin/php -q
 Version 2.1
./check_dns_authoritative ... 
	-H HOST
	-v Verbose
	-w thresholds warnning
	-c thresholds critical
	-m Mode:
		a - Check recursively if all NS respond authoritatively to a given DNS zone
		n - Check recursively if exist 2 or more NS servers of a given DNS zone
		r - Check if parent NS records match NS records from the authoritative server. (Stealth NS Check)
		s - Compare SOA registry between all authoritative NS of a given zone.