Please cherry-pick:

Please cherry-pick:
- departments, headquarters and branch offices cannot have a relation to
  employees as employess have a relation already to them. So if comparison of
  those entities come, this ends up in an endless loop with a stack overflow.
- the fix here is a bit simple and also a bit complex: relate those 3 entities
  to contacts (jcontacts-core.jar) and look in all employees related to the
  department, headquarter or branch office who have an equal contact record

Signed-off-by: Roland Häder <roland@mxchange.org>