Add .gitreview config file for gerrit.
Add .gitreview config file for gerrit.

Change-Id: Ic8133f316a7894cd38cd8df169480a4048c579d9

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