Picked from CE, from: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/18364

But includes the EE changes too. Among the required changes are dropping
of repository_storage_path from Geo tables.

Geo stored `repository_storage_path` in four models, which initially was
modeled after the interface of Gitlab::Shell rather than storing only
the needed data. Given this inferred data had no place nor need to be
stored I opted for deleting it.