Incorporate the Debian typo fixes where appropriate and make show_opt default message...

Incorporate the Debian typo fixes where appropriate and make show_opt default message clearer

Debian also incorrectly changes that the default for route parameters can
be specified by using "nil" instead of "default. The confusion is probably
coming from show_opt printing "nil" instead of "default". Change show_opt
to show "default (not set)" instead of "nil"

Original author: Alberto Gonzalez Iniesta <agi@inittab.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1468495519-25102-1-git-send-email-arne@rfc2549.org>
URL: http://www.mail-archive.com/search?l=mid&q=1468495519-25102-1-git-send-email-arne@rfc2549.org

Signed-off-by: Gert Doering <gert@greenie.muc.de>