More Firewall / Iptables Script Updates

I have updated my iptables scripts again.

This time fw_laptop got support for limiting logging in case of flooding, blocking of known-bad IP addresses (e.g. from DShield.org), optional blocking of certain outbound ports (e.g. X11 server, VNC, NFS etc.), and a few minor tweaks...

Thanks to Ryan Giobbi for several hints and comments. Further comments and suggestions are welcome!