!act,doc,rem,tes 3823 remove deprecated Props methods

- rewrite deprecated usages to their recommended counterparts
- TestActorRef now verifies mailbox requirements
- CallingThreadMailbox now exposes proper messageQueue type for
  inspection

akka-actor-tests/src/test/java/akka/actor/JavaAPI.java

@@ -48,14 +48,18 @@ public class JavaAPI {
     ActorRef ref = system.actorOf(Props.create(JavaAPITestActor.class));
     assertNotNull(ref);
   }
-
-  @Test
-  public void mustBeAbleToCreateActorRefFromFactory() {
-    ActorRef ref = system.actorOf(Props.empty().withCreator(new Creator<Actor>() {
+  
+  public static Props mkProps() {
+    return Props.create(new Creator<Actor>() {
       public Actor create() {
         return new JavaAPITestActor();
       }
-    }));
+    });
+  }
+
+  @Test
+  public void mustBeAbleToCreateActorRefFromFactory() {
+    ActorRef ref = system.actorOf(mkProps());
     assertNotNull(ref);
   }