Better fix for LOG4J2-605

  - Added @SensitivePluginAttribute for auto-censoring.
  - Doesn't help if your JNDI URI contains a password, though. ;)

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1587460 13f79535-47bb-0310-9956-ffa450edef68