Fix links to EchoServer.scala
API adjustments to ClusterClient, see #3264

* Message wrappers in ClusterClient, so that DistributedPubSubMediator
  is not leaking to the client api
* Register methods in ClusterReceptionistExtension, for convenience and
  clarity
Fixed misnamed barrier
Merge pull request #1357 from etaty/patch-1

Fix links to EchoServer.scala
also fix java/io.rst link to EchoServer et al
Merge pull request #1360 from drewhk/wip-3242-remotenodedeathwatchslow-failed-drewhk

Fixed misnamed barrier
Udp tests now use port acquired from a DatagramSocket #3245
Merge pull request #1358 from drewhk/wip-3245-udp-temporary-address-drewhk

Udp tests now use ports acquired from a DatagramSocket
RemoteWatcherSpec interference with real quarantining, see #3257
Increase time limits in CircuitBreakerMTSpec, see #3243
Allow a FromConfig router to be partly configured from code. See #3136
Use ScalaBuff 1.2.0-SNAPSHOT so the build works on windows.
Coordinate shutdown of ClusterDeathWatchSpec with messages, see #3255

* Added MultiNodeClusterSpec.EndActor for this purpose
* Changed UnreachableNodeJoinsAgainSpec to use the same
Merge pull request #1365 from akka/wip-3255-ClusterDeathWatchSpec-patriknw

Coordinate shutdown of ClusterDeathWatchSpec with messages, see #3255
Solve UnreachableNodeJoinsAgainSpec problem, see #3247

* UnreachableNodeJoinsAgain failed because of gated connection
* Removed default test value of retry-gate-closed-for, instead
  default from reference.conf is used, i.e. 0s
* deadLetters logging love
Merge pull request #1359 from akka/wip-cluster-client-api

API adjustments to ClusterClient, see #3264
Merge pull request #1366 from akka/wip-use-scalabuff-snapshot-so-build-works-on-windows-ban

Use ScalaBuff 1.2.0-SNAPSHOT so the build works on windows.
Move resolver so that all dependent projects find the artifact.
Additional coordination of shutdown in ClusterDeathWatchSpec, see #3255

* Added testconductor shutdown of actor system
* Renamed previous shutdown to exit
Merge pull request #1362 from akka/wip-3257-RemoteWatcherSpec-patriknw

RemoteWatcherSpec interference with real quarantining, see #3257