Check final version numbers after a `Restore:` directive has been actioned

[srcshelton]

The intent of the Restore directive is to provide a means which is as lightweight as possible to deploy a database dump into a running instance.

However, this also means that any --target-limit argument is ignored for cases where only an initialiser with a Restore directive is present. A final check should be performed in order to confirm that versions match.

Additionally, migratemetadataschema() should be executed after a restore.

Finally, the --help text should describe the --target-limit parameter.

[srcshelton]

94083a7 ensures that we don't ignore versions when running with '--init', runs migratemetadataschema() post-restore, and updates the '--help' output.