Update: Impove IP address processing code and logic.

Update: Impove IP address processing code and logic.

The TacocaT program exposed problems in the `f_network_is_ip_address()` function (which is now fixed upstream).

Remove the code that affectively works around the problem.
Replace it with a cleaner implementation.

This implementation explicitly handles extracting the IPv4 or IPv6 addresses (and port numbers) through dedicated functions.
Pass these to the `f_network_to_ip_string()` as appropriate.