Moving default location of .fwknoprc

[Strykar]

@mrash What are your thoughts on moving the default location of .fwknoprc from $HOME/.fwknoprc to XDG_CONFIG_HOME which would be $HOME/.config/.fwknop/.fwknoprc?

I can see how this might be perceived as breaking older installs and configurations and is trivially implemented by the user with --rc-file. If there is interest in this, I'd be happy to submit a PR.