added <IfModule mod_version.c> because gentoo has no mod version installed by default
added <IfModule mod_proxy_fcgi.c>

install/dist/lib/gentoo.lib.php
updated functions:
configure_postfix
configure_dovecot
install_ispconfig

added configuration for pureftpd versions greater than 1.0.50

added function get_host_ips() because gentoo does not provide IPs with "hostname --all-ip-addresses"

Add Debian 11 (Bullseye) to OS detection code in ISPConfig and update config for Debian testing (Sid)

- update user password with new hashing algo on login
- delete initial password from ispconfig sql file