Doc: use current schema version for uri:oozie:workflow:0.5 for all examp...

...les, except where refering to old/deprecated/removed config associated with prior-versions.

Currently, the client workflow XML documentation seems to refer to uri:oozie:workflow:<version>, where version is the current version when the doc was added, or when the feature was added, except when referring to deprecated features.

At the risk of creating a maintenance headache, I think I'd prefer that doc referred to the current schema version in all cases, except where referring to a removed/deprecated feature, which would refer to the old schema version.

At a minimum the Unified Credentials doc needs to change - it refers to 0.1, which does not include that feature.