IPv6 Addresses need to be enclosed in brackets

IPv6 Addresses need to be enclosed in brackets

This is a very lazy test for IPv6 instead of IPv4 addresses. The desired function, filter_var, does not appear to be available in the pfSense build I'm running.

http://php.net/manual/en/function.filter-var.php
Merge pull request #464 from darkain/patch-2

IPv6 Addresses need to be enclosed in brackets