Remove GetHome and CreateHome methods from the Storage interface #5271
Description
The GetHome and CreateHome methods should be removed from the storage interface: https://github.com/cs3org/reva/blob/master/pkg/storage/storage.go
The notion of a home should not be the responsibility of the bare filesystem drivers and they should live in the storage provider.
This change will facilitate the implementation of the storage drivers, since they won't need to understand if the calls needs to be relative to a home or not.