doc:Adding documentation for glusterfs and ovirt integration

Change-Id: Ie3b42a74198150c7e353d360ad38ac127d1a5ca2
BUG: 1086782
Signed-off-by: Kasturi Narra <knarra@redhat.com>
Signed-off-by: Humble Chirammal <hchiramm@redhat.com>
Reviewed-on: http://review.gluster.org/7772
Reviewed-by: Sahina Bose <sabose@redhat.com>
Reviewed-by: Humble Devassy Chirammal <humble.devassy@gmail.com>
Reviewed-by: Shubhendu Tripathi <shtripat@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Tested-by: Niels de Vos <ndevos@redhat.com>