Gentoo unattended installation script

Basically this is a batch script of the installation commands shown in the Gentoo installation manual for the x86 installation. At the beginning I added some code to create a typical LVM disk layout. You can configure a lot of things in advance by changing the options in the configuration file. So if you need to reinstall Gentoo on the same physical machine there is nothing more to do then to run the script. In order to take advantage of it you should have some experience with the normal Gentoo installation process. I also added a script for an unattended iptables installation with a default ruleset.