restructure remoting

- remove Remote, incorporate its few fields into RemoteActorRefProvider
- rename RemoteSupport to RemoteTransport to sync up with conf and
  the way we talk about it
- remove LocalAddress/RemoteAddress etc. and just have a final case
  class Address(protocol, system, host, port)
- split netty settings out or RemoteSettings into NettySettings
- split out from NettyRemoteSupport.scala: Server.scala, Client.scala,
  Settings.scala

plus a few fixes, including using the contextClassLoader when loading
the provider for ActorSystemImpl

akka-remote/src/main/scala/akka/remote/RemoteDaemon.scala

@@ -0,0 +1,80 @@
+/**
+ *  Copyright (C) 2009-2011 Typesafe Inc. <http://www.typesafe.com>
+ */
+
+package akka.remote
+
+import scala.annotation.tailrec
+
+import akka.actor.{ VirtualPathContainer, Terminated, Props, Nobody, LocalActorRef, InternalActorRef, Address, ActorSystemImpl, ActorRef, ActorPathExtractor, ActorPath, Actor }
+import akka.event.LoggingAdapter
+
+sealed trait DaemonMsg
+case class DaemonMsgCreate(factory: () ⇒ Actor, path: String, supervisor: ActorRef) extends DaemonMsg
+case class DaemonMsgWatch(watcher: ActorRef, watched: ActorRef) extends DaemonMsg
+
+/**
+ * Internal system "daemon" actor for remote internal communication.
+ *
+ * It acts as the brain of the remote that responds to system remote events (messages) and undertakes action.
+ */
+class RemoteSystemDaemon(system: ActorSystemImpl, address: Address, _path: ActorPath, _parent: InternalActorRef, _log: LoggingAdapter)
+  extends VirtualPathContainer(_path, _parent, _log) {
+
+  /**
+   * Find the longest matching path which we know about and return that ref
+   * (or ask that ref to continue searching if elements are left).
+   */
+  override def getChild(names: Iterator[String]): InternalActorRef = {
+
+    @tailrec
+    def rec(s: String, n: Int): (InternalActorRef, Int) = {
+      getChild(s) match {
+        case null ⇒
+          val last = s.lastIndexOf('/')
+          if (last == -1) (Nobody, n)
+          else rec(s.substring(0, last), n + 1)
+        case ref ⇒ (ref, n)
+      }
+    }
+
+    val full = Vector() ++ names
+    rec(full.mkString("/"), 0) match {
+      case (Nobody, _) ⇒ Nobody
+      case (ref, 0)    ⇒ ref
+      case (ref, n)    ⇒ ref.getChild(full.takeRight(n).iterator)
+    }
+  }
+
+  override def !(msg: Any)(implicit sender: ActorRef = null): Unit = msg match {
+    case message: DaemonMsg ⇒
+      log.debug("Received command [{}] to RemoteSystemDaemon on [{}]", message, path.address)
+      message match {
+        case DaemonMsgCreate(factory, path, supervisor) ⇒
+          path match {
+            case ActorPathExtractor(`address`, elems) if elems.nonEmpty && elems.head == "remote" ⇒
+              // TODO RK canonicalize path so as not to duplicate it always #1446
+              val subpath = elems.drop(1)
+              val path = this.path / subpath
+              val actor = system.provider.actorOf(system,
+                Props(creator = factory),
+                supervisor.asInstanceOf[InternalActorRef],
+                path, true, None)
+              addChild(subpath.mkString("/"), actor)
+              system.deathWatch.subscribe(this, actor)
+            case _ ⇒
+              log.error("remote path does not match path from message [{}]", message)
+          }
+        case DaemonMsgWatch(watcher, watched) ⇒
+          val other = system.actorFor(watcher.path.root / "remote")
+          system.deathWatch.subscribe(other, watched)
+      }
+
+    case Terminated(child: LocalActorRef) ⇒ removeChild(child.path.elements.drop(1).mkString("/"))
+
+    case t: Terminated                    ⇒ system.deathWatch.publish(t)
+
+    case unknown                          ⇒ log.warning("Unknown message {} received by {}", unknown, this)
+  }
+
+}