When a file on the server of an encrypted folder do
not have a matching entry on the JSON metadata, we
need to report an error and be done with the job
so that Sync status is not "running".
This eventually should cause the file to be removed
from the server as it can not be recovered anymore.
If the code was not complex enough syncing two tables
already started to give UNIQUE constrains errors on
simple sync operations, this also adds initial support
remote delete of an encrypted file