=act #3602 report `Connected` only when connection attempt was successful

Before this change, a client connection was always instantly reported as
`Connected`, even if the endpoint would never respond at all.

The reason is a weird behavior of OP_CONNECT and SocketChannel in the
JDK (observed in Linux):
 - a channel is always connectable before the connection is attempted
   (`channel.connect`). Selecting for OP_CONNECT before the `connect`
   call will instantly report connectable
 - even worse: after OP_CONNECT was reported true, also `finishConnect`
   will always return true, even if the connection wasn't yet established.
   That's probably the case because `finishConnect` is internally implemented
   depending on previous epoll results (on Linux).
small spelling fix
=pro,doc Update sbt-multi-jvm plugin to 0.3.8 and add sbt 0.13 docs
Merge pull request #1743 from akka/wip-upgrade-sbt-multijvm-ban

=pro,doc Update sbt-multi-jvm plugin to 0.3.8 and add sbt 0.13 docs
+per #3641 Storage plugin API

- Journal plugin API for storage backends with asynchronous client API (default impl: in-memory journal)
- Journal plugin API for storage backends with synchronous client API (default impl: LevelDB journal)
- Snapshot store plugin API (default impl: local filesystem snapshot store)
=act #3645 Make TcpOutgoingConnection actor handle UnresolvedAddressExceptions
Merge pull request #1751 from eligosource/wip-3641-storage-plugin-apis-krasserm

+per #3641 Storage plugin API
=rem #3621 Make Netty respect akka.daemonic setting
#3655 clu Stop sending EndHeartbeat after ack
Merge pull request #1758 from akka/wip-3621-make-daemonic-work-with-remoting-master-ban

(forward port) =rem #3621 Make Netty respect akka.daemonic setting
=rem #3643 Remove warning message from normal remote system shutdown.

Conflicts:
	akka-remote/src/main/scala/akka/remote/Remoting.scala
	project/AkkaBuild.scala
=act #3640 Fix how BalancingDispatcher apply mailbox configuration
Merge pull request #1761 from akka/wip-3640-fix-balancing-dispatcher-mailbox-config-master-ban

(forward port) =act #3640 Fix how BalancingDispatcher apply mailbox configuration
Merge pull request #1760 from akka/wip-3643-normal-remoting-shutdown-prints-warning-master-ban

(forward port) =rem #3643 Remove warning message from normal remote system shutdown.
!rem #3646: Optimize sending of Ack messages
Merge pull request #1754 from drewhk/wip-3646-sysmsg-ack-optimization-drewhk

!rem #3646: Optimize sending of Ack messages
Merge pull request #1759 from akka/wip-3655-stop-endheartbeat-patriknw

#3655 clu Stop sending EndHeartbeat after ack
Merge pull request #1732 from luc-at-jr/master

small spelling fix in Slf4jEventHandler.scala
!per #3652 Custom snapshot and persistent message serialization

- Protobuf serializer for Persistent message
- Configurable serializer for Persistent message's payload
- Configurable serializer for snapshots
+clu #3636 Revert join to uninitialized

* Revert the change introduced in
  https://github.com/akka/akka/pull/1738/files
* The cleanup/improvements aside of the actual
  feature is not reverted by this patch
* Clarify the documentation