SDK Listening Options

Resolving #393 (closed), should mostly be fine. Submitting as a draft as:

• Lacking input validation for the IP addresses (though --client seems to currently lack them, so might be fine as is).
• No IPv6 support, as the existing code uses inet_addr()
• Lacking translations.
• If it might be better to move the setting, as maybe users might find it a bit confusing.
• Currently using a std::string for the host, compared to the const char * taking functions for IP and name in NetworkClient.

Changes:

• Adds SetHost() and GetHost() to NetworkServer.
• Adds a UI option to set the Server Host in the SDK Server pane.
• CLI flags to start this by default.
• Autostart options.
• IPv6 support

Needs some further testing, especially on Windows, though it should work as is.

UI Changes: