FInternetAddrBSDIPv6::SetIp doesn't handle all valid IPv6 formats

Currently FInternetAddrBSDIPv6::SetIp(const CHAR* InAddr, bool& bIsValid) does not handle all valid formats of IPv6 addresses.

Need to rework the function to be more robust, and properly handle all (or at least more) IPv6 and IPv4 cases.

General test instructions:

Test IPv6 addresses one to verify all valid formats work:

Standard format.
[AAAA:BBBB:CCCC:DDDD:EEEE:FFFF:0000:1111] // With and without port :0123

Standard format with collapsed 0 sections.
[AAAA:BBBB::FFFF:0000:1111] // With and without port, and moving the double colon / including more or less sections.

Standard format IPv4 pass through.
[::FFFF:127.0.0.1] // With and without port.

IPv4 format
127.0.0.1 // With and without port.