Updated nova-network to correct info given
Updated nova-network to correct info given

Changed intro text, and final step, as per bug report. Slightly updated
wording and corrected bug number.

Change-Id: I91fa36d6bb1c4713f8d776e5ca71454c839f91e2
backport: havana
Closes-Bug: #1245960

kairoaraujo/openstack-manuals,gongysh2004/openstack-manual,potsmaster/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,potsmaster/openstack-manuals,kairoaraujo/openstack-manuals,Akasurde/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals,saeki-masaki/openstack-manuals,openstack/openstack-manuals,Akasurde/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,saeki-masaki/openstack-manuals,openstack/openstack-manuals,gongysh2004/openstack-manual