Change UserPasswort to accept Strings
Initial code for put-validation
Extract VersionKey to own class
Merge remote-tracking branch 'origin/master'

Conflicts:
	org.hive2hive.core.test/src/org/hive2hive/core/test/flowcontrol/common/PutUserProfileStepTest.java
	org.hive2hive.core/src/org/hive2hive/core/encryption/PasswordUtil.java
	org.hive2hive.core/src/org/hive2hive/core/encryption/UserPassword.java