* Rename config akka.event-handlers to akka.loggers
* Rename config akka.event-handler-startup-timeout to
akka.logger-startup-timeout
* Rename JulEventHandler to JavaLogger
* Rename Slf4jEventHandler to Slf4jLogger
* Change all places in tests and docs
* Deprecation, old still works, but with warnings
* Migration guide
* Test for the deprecated event-handler config
* ClusterSingletonManager
* ClusterSingletonManagerSpec multi-node test
* Use in cluster router with single master sample
* Extensive logging to be able to understand what is
going on
* Java api
* Add cluster dependency to contrib
* Add contrib dependency to sample
* Scaladoc
* rst docs in contrib area, ref from cluster docs
[RK: assembled commit log from original branch, squashed]
akka-contrib:
- an event handler which properly sets the ThreadID on log records
- a LoggingAdapter which does synchronous logging to j.u.l.Logger
- a small logging mixin for the aforementioned adapter
