2.2 DNS Exploration does not match code used in course

Hi, thanks for your work here. Interesting stuff.

I was commenting on your scripts in a duplicated repository and noticed that the course content scripts are different (specifically they do not include the 'ips' and 'successes' lists inside the SubdomainSearch and DNSRequest functions.). 

Also, the ReverseDNS function is structured quite differently.

Thanks again.