Add whois utility
This adds a whois client. Since there are alot of implementations of a whois client, I chose to follow the simple FreeBSD implementation.
This is a basic implementation, there is still lots of room for improvement. For example this doesn't implement a spam filter like the FreeBSD client. but I don't want to complicate things for now. Also, it would be very useful if we could use ArgParser for netutils. This would've made this utility a lot simpler. See this issue.
I haven't tested this in Redox yet.