cli_base: properly display boolean values
meta: added isPrimary to allow to specify a primary object in getByReference

This way e.g. the primary Host_Interface of a Host can be specified.
made Config structure for Unix->Linux->Debian to allow future configuration of Unixoid OSes like *BSD, OS X etc
added /etc/hosts generator Config/Unix/Net/Hosts/class.php, valid for every Unix (and possibly Windows, too)
Config_Unix_Net_Hosts: made it generate a valid /etc/hosts file