Fixed: FS#1755 - PHP notices during installation

install/dist/conf/centos52.conf.php

install/dist/conf/centos53.conf.php

install/dist/conf/debian40.conf.php

install/dist/conf/fedora9.conf.php

install/dist/conf/gentoo.conf.php

install/dist/conf/opensuse110.conf.php

install/dist/conf/opensuse112.conf.php

install/install.php

install/lib/installer_base.lib.php

install/update.php

server/plugins-available/nginx_reverseproxy_plugin.inc.php

server/plugins-available/squid_plugin.inc.php