EDIT

ref #9497 user account self registration: AccountCreationRequest only with email-address

• request tokens only with email address possible
• refactoring request tokens class hierarchy
• ... and token stores

cleanup

ref #694 add DescriptionElementService and move some methods

remove deprecated featureTreeService and featureNodeService and test classes

remove further featureTree and featureNodeService occurrences

cleanup and remove usage of feature tree service

ref #9497 AccountRegistrationService tesing for existing usernames & adding exist check methods to dao

cleanup and renaming some functional test classes (cont. II)

cleanup and renaming some functional test classes (cont.)

cleanup and renaming some functional test classes