=act - Refactored the BatchingExecutor to support both managed blocking and not.
=clu #3941 SurviveNetworkInstability ignore leftover pings
+act,mul #3948 add MultiNodeSpec.startNewSsytem() and system.abort()

abort() currently only changes that remote-deployed child actors are not
waited for during termination (because that would not change anything);
it is still a different operation than shutdown() since it changes what
you are guaranteed to observe after termination.

testConductor.shutdown(..., abort = true) uses this mode of termination.

improve MultiNodeSpec to allow injection of deployment configuration
into arbitrary actor systems

include number of received elements in the timeout failure message for
TestKit.receiveN
+act #3949 add LoggingReceive.withLabel

def someState = LoggingReceive.withLabel("some state") {
  case msg => ...
}
=act,rem #3930 part 1: remote daemon watches parents

also stop child actors which are replaced in VirtualPathContainers
=rem #3930 part 2: track UID of associated systems

for proper clean-up of the old association (including the writer) when
the restarted system connects before the old association has been torn
down
=per #3915 Make become work during recovery for EventsourcedProcessor et.c.
Merge pull request #2091 from akka/wip-3915-eventsourceprocessor-become-during-recover-master-ban

(Forward Port) =per #3915 Make become work during recovery for EventsourcedProcessor et.c.
=cam #3929 updated apache camel dependency to version 2.13.0
+act,sam,doc #3940 Added receive setter for Java Lambda actors

* Added a setter for Java lambda actors to "hide" the not so nice looking type signature of the "receive" method.
* Updated docs to reflect the changes.
* Converted samples to use the new setter.
Merge pull request #2090 from akka/wip-remoting-multi-fix-∂π

Wip remoting multi fix ∂π (broken commits apart properly)
=doc #3917 include all reference.conf
Merge pull request #2094 from akka/wip-3940-add-sugar-to-abstract-actor-master-ban

+act,sam,doc #3940 Added receive setter for Java Lambda actors
+con #3937 Start ShardCoordinator again after PersistenceFailure

* Add supervisor level that will start the ShardCoordinator again after
  a configurable backoff duration
* Make the timeout of SharedLeveldbJournal configurable
* Include cause of PersistenceFailure in message of ActorKilledException
add links to reference.conf to docs
Merge pull request #2096 from akka/wip-forward-docs-∂π

=doc #3917 include all reference.conf
=per #3933 Correction of seq number logic for persistent channel

* Problem when using PersistentChannel from Processor
* When the seq numbers of the sending processor and the seq numbers
  of the PersistentChannel was out of sync the PersistentChannel
  did not de-duplicate confirmed deliveres that were resent by
  the processor.
* There is a hand-off in the RequestWriter that confirms the
  Processor seq number, and therefore the seq number of the
  RequestWriter must be used in the ConfirmablePersistent from
  the RequestReader
* More tests, covering this scenario
=doc #3954 Clarify how to use snapshots with Maven
=doc #3924 Doc how to be notified when recovery completed
Merge pull request #2097 from akka/wip-3937-sharding-persistent-failure-patriknw

+con #3937 Start ShardCoordinator again after PersistenceFailure