Continued with user profile data:

Continued with user profile data:
- renamed changeFoo() to doChangeFoo() to match with naming convention
- added doChangePersonalData() which throws a checked exception
- that method does currently only check if the user is logged-in and if the password matches
- the resulting error message would be not user-friendly, so better added a validator which outputs a new localizable message
- added method ifCurrentPasswordMatches() which uses UserUtils to validate the entered password
- renaming interface applied
- updated juser-core.jar
- added jcoreee.jar