Clarified the docs and help screen about what a 'cmd' is

Clarified the docs and help screen about what a 'cmd' is

This also changes the descriptions of several options to note that they accept
a "command"; change the description of --client-connect and --client-disconnect
indicate that the temporary file's path is passed as the last argument to the
command, not the first argument; and Adds a description of --route-pre-down to
the descriptions of the other --route options.

[DS: This patch is based on parts of the options.c.diff and the complete
     openvpn.8.diff patch sent to the mailing list - where these docs changes
     are merged together into this patch]

Signed-off-by: Jonathan K. Bullard <jkbullard@gmail.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: CAEsd45RkyJw6yUk1Jwkip70HkCjKYoU+V=do3N7SH7JOaHBZdw@mail.gmail.com
URL: http://article.gmane.org/gmane.network.openvpn.devel/6194
Signed-off-by: David Sommerseth <davids@redhat.com>