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/test/scala/akka/remote/RemoteRouterSpec.scala

@@ -20,7 +20,7 @@ object RemoteRouterSpec {
 class RemoteRouterSpec extends AkkaSpec("""
 akka {
   actor.provider = "akka.remote.RemoteActorRefProvider"
-  remote.server {
+  remote.netty {
     hostname = localhost
     port = 12345
   }
@@ -44,7 +44,7 @@ akka {
 
   import RemoteRouterSpec._
 
-  val conf = ConfigFactory.parseString("akka.remote.server.port=12346").withFallback(system.settings.config)
+  val conf = ConfigFactory.parseString("akka.remote.netty.port=12346").withFallback(system.settings.config)
   val other = ActorSystem("remote_sys", conf)
 
   override def atTermination() {