Transactional processing: error in renaming atomic-suffix will delete all files

When an error in the renaming phase of the atomic transfer occurs all files are deleted due to a wrong process sequence.

Actual (and wrong): transfer from source to target, delete source, rename on target.

New (and better): transfer from source to target, rename on target, delete on source

Improvement (not yet implemented): transfer from source to target, rename/archive on source, rename on target, delete on source