Data reorganization for Eon Mode migration

In Vertica 10, the migration from enterprise to eon will take an n-node enterprise database (which is segmented n-ways) and migrate it to an n-shard eon database (also segmented n-ways). Since the count doesn't change, we don't actually have to make modifications to the data files themselves. The migration metafunction will copy the data files unchanged from the local enterprise database to your chosen communal storage location, and then modify (for the most part, any storage-related catalog objects will need to be modified to include eon shard information) & upload the catalog. Since catalog size is dwarfed by the raw data size this is still not too bad.

In advance of running the migration at all, you will have to fully rebalance your eneterprise database since we're depending on that n-way segmentation during the migration process.

For a few more details about migration, there's also a good forum post here: https://forum.vertica.com/discussion/241348/migration-from-enterprise-to-eon-mode#latest