update versioning docs

[John Dickinson]

doc/source/api/object_versioning.rst refers to old (pre-middleware) ways to enable versioning. These instructions need to be updated (and the rest of the document audited too).

[Thiago da Silva (thiagodasilva)]

How about we remove that page all together? Comparing http://docs.openstack.org/developer/swift/api/object_versioning.html and
http://docs.openstack.org/developer/swift/middleware.html#module-swift.common.middleware.versioned_writes , the information there looks very very similar, so instead of duplicating information, I'd just update what's in the middleware source code and remote the doc/source/api/object_versioning.rst

Thoughts??

[John Dickinson (notmyname)]

The API docs should be how to use it from an end-user perspective. No need to have configuration and cluster-enablement there.

The middleware docs should refer to the API docs for usage and should cover how to deploy, migrate, configure.

I think there is a role for both docs.

[Thiago da Silva (thiagodasilva)]

The api-docs [1] were updated as part of the history mode patch to object versioning. I think this is now ready to be marked as 'Fixed released'

[1] - http://docs.openstack.org/developer/swift/api/object_versioning.html