Add backups to wiki server.

Change-Id: Ia0ec8657aedc4bafda396255b011382382d7287c
Reviewed-on: https://review.openstack.org/19827
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Approved: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins