Currently on a system without xterm or konsole (like fresh
Ubuntu install) the fsck check will not launch. Added
gnome-terminal as an alternative and fixed an issue where
konsole will always error out as --title and --caption are
no longer valid arguments.
Previously the error message was simply "xterm not found", so
new LangString LINUX_EX2MSG_TERMINALNOTFOUND was added to let the
user knows which programs they need to get the feature working.
