Adds swift user to the Object Storage Service install steps

backport:havana
Change-Id: I9f335751e9476fcd13ce2cd2e714a64045fdc897
Closes-bug: 1263649
(cherry picked from commit c65d643e9ac3db0d59da0339014939e8f565efa0)
Fixed database configuration steps for Block Storage

I changed the database configuration steps for Block Storage from the
legacy 'sql_connection' key under the '[DEFAULT]' section to the new
'connection' key under the '[database]' section common to other
services. I also added a note for Ubuntu users to add the '[database]'
section header if not included with the default "cinder.conf" file.
This patch covers both the controller and storage nodes.

Change-Id: I12fdb940c0831c052bc5a4a0328112a72e505d34
Closes-Bug: #1245880
Merge "Fixed database configuration steps for Block Storage" into stable/havana