Restore tenants using the configured paths

/admin/restore always treats the restore as a tenant database (system
doesn't make sense here) and uses the appropriate paths for data, logs,
and indexes.  Kept the destination param with support for relative paths
as an override for backwards compatibility with Raven.Server and Tests.
Merge branch 'master' of https://github.com/barryhagan/ravendb
Moving setting to more appropriate place
Fixing issue with LoadDocument + SelectMany