Don't cherry-pick:

Don't cherry-pick:
- added missing createManaged() methods for Department and HireableJobPosition
- You can do someInstance.getClass() to avoid importing the implementing class
  instead which is more flexible and allows other implementations
- renamed BaseJobsDatabaseBean to BaseJobsEnterpriseBean and moved to proper
  package
- renamed JobPosition to HireableJobPosition (maybe tpzo?)
- renamed classes with "Headquarters" in it to "Headquarter" as "s" is plural
  and should be only used for utility classes
- added missing imports of utility classes
- the registration bean does no longer have isEmailAddressRegistered() and
  isUserNameRegistered() as this exists in user bean, fixed all occurances

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