Clients can log in with encrypted passwords

https://issues.apache.org/jira/browse/KARAF-5316 introduced a regression in Karaf 4.2.0, that clients could log in using encrypted passwords. So for example, if you enable JAAS encryption, and run bin/client it logs in without prompting for a password - as the JAAS code falls back to comparing the received (encrypted) password directly against the stored value. In 4.1.x, it always prompted for a password when encryption as enabled. IMO the 4.1.x behavior was the correct one.