Add support to ignore specific options.

Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1376640664-26379-1-git-send-email-arne@rfc2549.org>
URL: http://article.gmane.org/gmane.network.openvpn.devel/7799

Signed-off-by: Gert Doering <gert@greenie.muc.de>
Add a note what setenv opt does for OpenVPN < 2.3.3

Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1376640680-26468-1-git-send-email-arne@rfc2549.org>
URL: http://article.gmane.org/gmane.network.openvpn.devel/7798

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