Ensure data directory restorations guard on chef server version

[ryancragun]

We should record the Chef Server version in the backup manifest and guard against restoration unless the Chef Server is of the same Major and Minor version.

[ryancragun]

I added support for slurping up the upgrade migration level. If we start tracking the chef-server version in the manifest we can trigger an upgrade during restore if the chef-server version is newer than the backup version.